The Anatomist Chapter 1, a sherlock fanfic

James Joseph Moriarty was born in Galway, in 1976. His birth certificate no longer exists.

If it did, it would list his father's name (Dr. Joseph Arthur), his mother's (Mrs. Elizabeth Anne), and his birth weight (2.7kg). It would not tell you that his eyes were blue, or that he entered this world as he will leave it – howling.

It would not tell you that five minutes later his mother (Mrs. Elizabeth Anne) gave birth to a daughter, his sister. His twin. The records of her birth burned with his, but if they hadn't, you would know her name.

Mary Elizabeth Moriarty was born in Galway, in 1976.

They will call her Molly.

Their name was not Moriarty, not then. Moriarty is a cipher, a small piece of a larger puzzle; Jim chooses it when they are twelve, after their mother dies and their father is sent away and they become penniless orphans, like in a storybook. He writes the name above the creased fold of a brown paper bag, the nearest paper to hand. His pen shakes, excitement like a flame behind his eyes.

Jim and Molly Moriarty, he writes, with long, heavy loops on the l's and y's. She takes the biro and copies it out carefully, her handwriting small and neat and utterly unremarkable. Jim and Molly Moriarty, she writes, over and over again, covering the wrinkled brown paper with their new name, and when Jim takes it from her the ink smears under his fingers.

This is what we really are, his smile says. This is what we become.

They will use many other names. This is the only one they remember.

Their father is a professor of mathematics at Trinity, and when he swings Molly into his arms at the end of the day she tastes the chalk dust on his clothes, like desert sand under her tongue. Sometimes she sneezes into his collar, and he laughs.

"Hello, my little mouse," he says, whispers into her ear before scooping Jim up in his other arm and spinning them close, in a tight circle down the length of the hall. Their mother looks on from the doorframe, her tired face fond.

(Jim doesn't like to be spun, doesn't like to be carried or embraced or confined, but he's good at pretending. Only Molly can see the edge to his smile.)

"Now then," her father says, a child on each hip, "what does the little mouse want for supper?"

"Cheese," Molly answers, quite seriously. "Mice eat cheese."

"And chocolate biscuits," Jim adds with a charming, gap-toothed grin. "Mice go mad for chocolate biscuits." Her parents laugh, but Molly doesn't understand why. Mice will eat anything, she thinks, that's why they're pests. Her mother sets traps and everything.

"Don't frown, little mouse," her father says, kissing her cheek. "You'll get your cheese."

"Will it be in a trap?" Molly asks, picturing the small, furry bodies and their small, snapped necks. She's seen them in the traps, still twitching.

Her parents laugh again, their eyes flashing in the lamplight.

Molly likes making them laugh; she'd like an answer to her question more.

Molly has soft, mouse-brown hair that curls around her ears, rarely tangling. She is small for her age, with quick-pale fingers and a quiet, nervous disposition, and she hides in linen cupboards, under tables and behind dust-heavy curtains. She learns not to sneeze.

People think Jim is the clever one, and he is clever. He always knows just what to say and just how to say it, and when their father's friends from the university come to dinner they watch Jim's proofs and equations unfold with awe in their whiskey-fogged eyes.

Impressive, they say. Remarkable. The word prodigy gets thrown around quite a bit, though Molly had solved the same equations that afternoon after school, and she'd shown her work.

But Molly hides from guests, from teachers, from her mother and her father. She doesn't hide from Jim, because he will always find her, and because he doesn't like having to look. If she tries he will crowd in beside her, too large and too warm and breathing too loud, his knees sharp against her side, and he will say, "If you ever run away from me again, little mouse, I'll pinch you until your arm turns blue."

"If you ever turn my arm blue," she whispers back, "I'll bite your fingers off."

"Yum," Jim says, smacking his lips, and then their mother finds them, laughing like jackals in the darkness at the depths of the broom cupboard.

Molly is eight years old when she sees her first human corpse.

She's hiding in the narrow space beneath the stairs when the kitchen door creaks open, filling the hall with the midnight summer smells of the alley outside. Two man-shaped shadows walk in, their footsteps loud in the sleep-silent house. The second shadow has her father's neat beard and narrow shoulders; the first is taller, broader in the waist and chest.

Her father flicks on the kitchen light, and Molly sees the knife in his hand.

"Fuck, Joe," the broad man says, his voice shaking. He has red hair and a dark red beard and a red, flushed face. He watches the knife, his eyes wide and white with fear. "I don't know what they told you, but it weren't me that nicked it, I swear. I know better than to take what isn't mine."

Her father's smile has a familiar edge. "An interesting defence, for a thief."

"I don't steal from you," the broad man says, close to tears. "You know I don't."

"Yes," her father says, not unkindly. "I do." He takes a step closer to the broad man, and Molly watches as his grip on the knife changes. Tightens. "But unfortunately for us, Mike, the rest of the city lacks our nuanced grasp of the situation. They think you got the better of me. They think you won. And that's not something I can let them think for long."

Her father's knife slides neatly into the broad man's belly, splitting him open from stomach to sternum. The man spills across the kitchen floor, collapsing in a sudden deluge of dark blood and the darker, splattering shadows of his intestines. It takes him a moment to die (shuddering silently like a mouse in a trap) and Molly meets his eyes, just before the light in them dims.

Her father stands over the body, watching the blood flow over the white linoleum. It touches the toes of his shoes. "Molly, come here."

She crawls out from beneath the stairs and walks into the kitchen. The floor is cool against her bare feet; she buries her hands in the pockets of her dressing gown. Her father sits at the kitchen table, sets the knife down beside the fruit bowl, and lifts her into his lap.

"So," he says, his blood-soaked sleeve damp against her ribs as he holds her close. "What's a little mouse doing out of bed at an hour like this?"

"I couldn't sleep," Molly says. She frowns at the body on the floor. "Why didn't he try to stop you? He was bigger and stronger."

"Such a good question," her father says, and drops a kiss on the top of her head. "What do you think, Mol? Why couldn't he stop me?"

She thinks hard, remembering the look on the man's face when the light flicked on and he first saw the knife. The way his hands shook as he held them out in futile supplication. Her eyes fix on the broad man's body, on the growing emptiness inside him.

(She never imagined we could contain so much. She wants to see more.)

"He was afraid of you," she says finally. "Not afraid of the knife, or of getting hurt, or even of dying – he was afraid of you." She turns to meet his eyes. "Am I right?"

"My little prodigy," her father says, and tucks a loose strand of hair behind her ear.

That autumn, Jim starts bringing her dead birds.

"I could save one of the live ones for you, if you want," he says, which is uncharacteristically generous of him. (Jim will never really learn how to share.) "They're a lot more fun."

Molly shakes her head and snaps on a pair of plastic gloves. "I learn more from them when they're already dead," she says. She holds out her hand. "Scalpel."

Jim passes her a sharpened kitchen knife. "I've been thinking about trying for a cat."

Molly pauses, her knife poised above the wren's still chest. "That would be interesting. A cat's anatomy would be a lot more like the real thing than a bird's."

Jim leans over her makeshift autopsy table, propping his chin up on his hands. He grins at her. "Also, cats can scream."

Molly frowns. "Birds can't scream?"

"I've never heard one, and not for lack of trying."

"Fascinating," Molly says, and moves the tip of her knife to the wren's throat.

The first time Jim tries to kill her, it is a week after their eleventh birthday.

They are upstairs, sprawled across the landing of their long, narrow house and working through the problem set their father had passed them that morning at the kitchen table, over toast. Afternoon sun streams in through the windows, catching dust.

Jim lies on his stomach, his chin resting on the edge of his open notebook. "I'm done," he trills. "I finished first." He tilts his head to the side, looking up at her. "I always finish first, have you noticed?"

Molly looks down at his work. "Actually, I haven't." She points with the sharpened end of her pencil. "This is wrong. You rushed through it; I can tell."

He slaps her across the face, hard enough to stun her for a moment while he twists his fingers into her hair and drags her to the edge of the landing. "I'm not wrong," he says, and pushes her down the stairs.

She fractures her right leg and dislocates her shoulder. She tells the doctor that she tripped over the rug and fell, that she was clumsy and it was her own stupid fault. She laughs with him, like it's just a joke with a painful punch line.

Her father can see through lies like other men see through glass. He stands by her side, one hand on Jim's shoulder, the other on hers. He doesn't contradict her story.

That night Jim sleeps in a chair beside her bed, the crown of his head against her hip. "I don't know how I'd live without you, Mol," he says, to the dark. "I don't know how I'd breathe."

"With your lungs, probably," Molly says, and reaches past the pain in her arm to link her fingers through his.

Four months later, Jim is halfway through a story about yesterday's rubbish football match when his speech begins to slur.

"Something's wrong," he murmurs, mumbles, spits, his head in his hands and his eyes open wide, staring at the air before him in fear and horror and (delicious) surprise. "Mol," he says, "something's wrong, I can't see—"

It starts with slurred speech and blurred vision and the sudden droop of his left eyelid, and the doctors say stroke and neuromuscular disease and descending paralysis before they stick needles in his spine and tack pictures of his brain to the wall. They mutter together in soft voices like cattle lowing in open pastures, and her parents' knuckles grip white with fear.

The next morning, Jim can't lift his arms.

"It'll be your legs next," Molly tells him, when the adults finally leave them alone in his hospital room. ("Poor dears," one of the doctors says, "they seem very close," and her father covers his mouth as he nods.) She sits high on the edge of his bed, her legs crossed at the ankles, her hands in her lap. "It'll be your legs, then your abdomen, then your lungs. You'll suffocate, probably."

Jim tries to grin at her, but his lips twist strangely, to the side. "Poison," he slurs, his exhale like a laugh. "How like a girl."

"I think," she says, "that I'll take that as a compliment." She swings her good leg back and forth, out and in, and the hospital bed creaks beneath her. "I slipped a small dose of botulinum toxin into your juice. I could teach you how to make it, if you want."

He gives her a weak nod, and she smiles, bending down to drop a kiss on his forehead.

Molly tells the doctors about a funny-shaped tin of beans she'd found behind the supermarket, a tin Jim had eaten from on a dare. One botulism antiserum and five long weeks of recovery later, Jim is strong enough to walk again.

She lends him her crutches.

They don't mention the poisoning again until university.

"What if I hadn't figured it out?" he asks one evening, over a curry. He has sauce on his chin; she wipes it away with a neat swipe of her thumb. "What if I hadn't known it was you?"

She shrugs. Wipes her thumb on the tablecloth. "Then you would have died. That was the whole point of the exercise."

She never doubts that he loves her. In moments like these, she can see it written in his eyes.

When they are twelve, their mother goes down to the kitchen in the middle of the night, puts the kettle on for tea, and shoots herself in the head.

Molly has never seen her father cry before; he pushes them back, out of the kitchen, away from the blood spilling slowly across the white linoleum floor. Most of her mother's face is missing, is spread across cabinets and clean dishes and the rug at the foot of the sink. Her father tries to cover their eyes, to turn them away.

"No," she says, her fingers fisted in his shirt. "No, I want to see—"

The teakettle whistles.

The day before she died, their mother turned over enough evidence to the Garda to send their father to prison for the rest of his life. They take him from the house not long before dawn, his hands cuffed behind his back. His shoes leave bloody footprints in the hall.

"I'm glad she's dead," Jim says, sitting on the stairs, Molly's hand clutched in his. "I wish she'd died slower."

The gardaí are taking their house apart, piece-by-piece. Searching for evidence. Preserving the crime scene. One garda looks up from his camera and gives them a stunned, unsettled look; he heard.

"My brother's in shock," Molly says in a choked, teary voice. "Has anyone talked to our grandmother? I don't think he'll leave with anyone but her."

"I-I'll go check for you," the man says, and flees to the still-bloody scene in the kitchen. Molly twists Jim's fingers hard between hers, and he hisses in pain.

"The hell—"

"You need to learn to shut up," she says, and curls into his side, her head resting on the sharp bones of his shoulder. The air in the house smells sickly-sweet, thick with the stink of strangers and mud from the street outside; she buries her nose in Jim's collar, breathes in laundry soap and boy. "We have to be invisible," she says, to his throat. "We have to disappear."

His arm draws tight around her shoulders. "Or what?"

Or they'll catch us, she thinks, and closes her eyes against a camera's flash.

One week before the explosion in Baker Street, Molly asks Jim what he remembers about their mother.

"An odd question," he drawls, lounging in his chair with his arm draped over the stiff-plastic back. It's meant to be their first date, a quick lunch in the hospital canteen and the opening act of the ridiculous little psychodrama Jim's staged for the benefit of his favourite nemesis. His posture is all wrong, out of character and out of place; Molly wants to kick him in the shins.

Instead she takes a bite of her salad. "We don't have to talk about it," she says, innocently. "Not if it upsets you."

He leans forward, his eyes narrowed. "It doesn't upset me."

She shrugs. "All right."

"It doesn't." He gives her a forced, flirtatious grin. To their co-workers at the next table, it probably seems perfectly charming; up close it looks like a grimace. "I remember that she did the crossword in the paper every morning, in ink. I remember that she chewed peppermints after dinner. I remember that she wore her hair long, like yours, and then I remember that she betrayed our father and shot herself in the fucking face before he could do it for her."

Molly nods. "That's what I remember, too," she says, and kicks him gently under the table.

They leave Ireland the day after their mother's funeral.

Their grandmother's house in Brighton is wide windows and deep carpets and pale trim, and the distant sound of the sea keeps Molly awake and red-eyed for the first year. It is never home.

But she finds that there are just as many places to hide in Brighton as there were in Dublin (behind books, behind schoolwork, behind a smile) and she adjusts. Slowly.

Jim does not.

He has never been anything but universally adored, but now the boys at school call him poof and freak and pitch their voices high and lilting to mimic and mock and they have no idea, he says, no fucking idea what he could do to them. What he's done before.

That spring, four cats and one dog go missing in their neighborhood. Molly and Jim help in the search, stapling lost: reward signs to telephone poles and community boards. Jim smiles all the while, and their gran calls him a good, sweet boy.

Molly learns a lot that first year in Brighton.

The chair beside her creaks. "Are you really reading that?" a deep voice asks, and Molly squeaks in surprise, her head snapping up from her book.

A tall, fair-haired boy sits beside her, his arms folded in front of him on the library table. He's familiar, two years above her and popular despite his awkward height and slightly spotty face. His expression is sheepish.

"Sorry," the boy says. "Didn't mean to startle you."

"No, it's fine," she says, her hands fluttering to her lap. "It's just – people don't usually notice me. In the library, I mean. When I'm reading." She blinks at him. "What did you say?"

The boy smiles. "I asked about your book." He leans close, his shoulder almost brushing hers. He frowns at the diagram on the open page. "Is that meant to be a heart?"

"A spleen, actually." Off his puzzled look she adds: "Not a very healthy one."

"Oh. Cool." He sits back a little, and she starts to breathe again. He smells like chlorine and stale crisps, and her heartbeat thunders in her ears. He asks a question; she doesn't hear it.

"Sorry?" Molly says, and the boy laughs.

"I said, do you want to be a doctor?"

"Oh, yes," she says. "Well, a forensic pathologist, really. They cut up dead people and find out how they died." She bites her lip. "That sounds weird, doesn't it? That sounds really weird."

"No, it sounds brilliant. Creepy, but brilliant." He looks down at the spleen again, his long, friendly face suddenly shy. "I notice you."

"What?"

"You read here every day after classes. Mostly medical books, or maths, but sometimes you play chess with your brother. I think you usually let him win, just to avoid the fit he throws when he loses." His mouth quirks at the corner. A small, self-mocking half-smile. "You said no one notices you, but I do. I notice."

"Oh," she says, stunned. "I—"

"My name is Carl," the boy says. "Carl Powers."

"I'm Molly," she breathes, already lost in love.

Twenty-one years later, she walks into the lab at Barts and sees Carl's trainers sitting on the table, next to Sherlock's microscope. They still have Sussex dirt caked on the soles.

(Jim's hand settles soft between her shoulder blades, and she smiles around the word romance.)

Carl kisses her for the first time on the front steps of her grandmother's house. She has sand in her shoes, between her toes, and his mouth tastes like salt. Like chips and the sea.

"Can I?" he says, and she nods, quickly, arching up to meet him as he bends and it's a bit awful at first, in a wonderful way. His mouth is too big, or hers is too small, and she would disappear into the ground, if she could. But then his hand cups the back of her head, long, steadying fingers and his face above hers and her heart breaks for him, a little.

He's a sloppy kisser. She doesn't mind.

"Well now," Jim says from the open door, his voice high and cutting and oh-so-amused. "Isn't this a pretty picture?"

The kiss ends, abruptly. Molly doesn't open her eyes. "Carl," she says. "You know my brother Jim."

"Uh, yeah," Carl says, and she can tell by his voice that he's one of the boys from school, one of the boys who call Jim queer and pour spoilt milk into his gym bag. He takes a step away from her, his arms hanging awkwardly at his sides. "Hey, mate."

Jim gives the other boy a long, pitiless look. "How very nice to see you again, Carl," he says, and for a moment he makes no effort to hide the emptiness in his eyes. Carl flinches, and Jim's lips twist in a wide, hollow smile. "Mol, you're late for tea. Gran's waiting."

"I'd better go," Carl says, and takes a stumbling step backward. "I'd better – I'll see you Monday, Molly. At the library?"

"The library," Molly agrees, and then he's gone, down the steps, onto the pavement, and away. Jim wraps his arms around her waist from behind, his chin resting on her shoulder. Together, they watch Carl go.

"I bet you'd like to cut him open," Jim says, his breath warm against her ear. "I bet you'd like to see inside."

She folds her hands over his. "I bet you'd like to watch."

He laughs. "My little mouse," he says. "You know me so well."

Their grandmother calls, and they go inside for tea.

The day Carl drowns in a London pool, Molly watches the tournament from the sidelines. Her throat is sore with the thick taste of chlorine, her voice hoarse from cheering. She has their lunches in a brown paper bag, sandwiches and crisps and two still-cold cans of ginger beer. She clutches it to her chest as she shouts, rises to her toes to see over the crowd and cries faster, Carl, you can do it. I know you can.

He jerks in the water, and for an odd, weightless moment she thinks he's heard her, thinks he's about to lift his head from the water and reply. Then he jerks again, and is still.

He's dead by the time they pull him from the water. His head lolls gently to one side, and she looks into his open, sightless eyes. His left eyelid droops, slightly.

The bottle of eczema medication is still in his locker, tucked into one of his trainers. She takes them both – dumps their lunch into the bin and hides the trainers in the paper bag. They fit neatly under her arm as she slips back into the crowd.

Jim always forgets the details.

"It has to be done," Jim says, twenty-one years later. His forehead touches hers, and their breath mingles. "He's too close. He sees too much."

"He doesn't see me," Molly says, as if she thinks that might be enough to keep him safe.

It isn't.

Two days after Carl dies, Molly skives off school and takes the train back to London.

The pool is not a crime scene. (Tragic accident, the papers say, and no one disagrees.) Her footsteps echo on the tile as she walks, the soft sounds of the filters loud in the silence. She crouches by the edge, and her fingers brush the water, rippling the light beneath.

"No, listen to me," a boy's voice says from the corridor outside. She hears two sets of quick, steady footsteps, coming closer. "Powers had no history of seizures or neuromuscular disorders; he was in perfect health, aside from his skin condition and a mild case of gastroparesis. These facts, coupled with the as-yet-unexplained disappearance of the boy's shoes—"

"Look, kid," a man's voice says, and two silhouettes appear in the frosted glass of the pool door: one short and heavy-set, the other tall and long-limbed. The man clears his throat. "Did you know Carl Powers?"

"No, of course not," the boy says, crisply. "I read about him in the papers."

The man rubs his hand over his forehead, his posture weary and long-suffering. "Then you read that we have no reason to suspect foul play. Carl Powers' death was a tragic accident."

"Tragedy is not an explanation, Detective Inspector – it's empty sentiment disguised as analysis."

"That may be," the man says, "but in the end it's all we've got." He gives the boy a paternal pat on the shoulder; the boy just barely stops himself from flinching away. "I've real work to do, kid. Don't bother me again."

The man walks away. The boy waits unmoving until his footsteps fade down the corridor, then he turns abruptly and pushes through the door into the echoing silence of the pool. His eyes fix on hers.

"I know you're not a student here," the boy says. "Don't bother lying about it."

He's tall, sharp-boned and scarecrow thin – a sudden growth spurt in the last two months, she thinks, and his voice hasn't quite finished changing so he can't be more than a year older than she is. His hair is dark, curling, and a little too long; his clothes are well made, expensive but treated casually – he's burnt a small hole in his left sleeve and there are spatterings of chemical stains on his right. Add in the posh accent, and he may as well have the words public school swot written on his forehead in ink.

"You're right," Molly says. "I'm not a student here." She sits at the edge of the pool, hugging her knees to her chest. "Neither are you, though."

He frowns. Walks around her, his hands in his coat pockets. "You're not from London. I'd say Sussex, judging by the length of your vowels, with a faint yet unmistakable Dublin undertone. But you haven't lived in England long – you've shed your accent deliberately."

"Your shoes are too tight," she says, "and they pinch at the toes. You've outgrown them already. Probably your second pair this month."

He stops walking. "You knew Carl Powers."

"Yes," she says. "He was my boyfriend."

An odd, focussed expression passes over his long face. "I'm sorry for your loss," he says with great concentration, like it's something he learnt from a phrasebook he bought before travelling to a foreign country.

I'm fascinated by the customs of your people, Molly thinks, a little hysterically, and starts to giggle.

The boy stiffens. "Did I say something funny?"

"No, no, sorry," she says, and lets out one last little hiccupping laugh. "I just – it's an odd thing, grief. Hits you in unexpected ways." She stands, rubbing at her eyes as if she's been crying. (She hasn't. If she does, Jim will know.) "You don't really think someone hurt Carl on purpose?"

His head tips to one side. "Don't you?"

The boy's eyes are cold and pale and their pull is like gravity (like the tide tempting her to sea) but Molly has always been able to lie, when it matters. She folds her hands into her sleeves and gives him a carefully fragile smile. "He was just a normal kid," she says. "Why would someone want to kill him?"

The boy sniffs and turns away; she's lost his attention. "Why is only useful," he says, "when it leads you to how."

You're wrong, she wants to say, and more than that she wants his eyes on hers again, wants to be the focus of his gaze and the diamond-sharp scalpel of his mind. She wants to know what he'd see, inside.

(She thinks she would stop hiding, for him. If he ever bothered to look.)

"Oh," she says in a small, startled voice, like the sound a mouse makes just before the trap snaps shut, "I should go. I'm going to miss my train."

He frowns, his gaze turning briefly inward. She can almost see the timetable reflected in his eyes. "You already have," he says, and walks away. The pool door swings shut behind him.

She'll spend the next nineteen years wishing she'd asked his name.

He's halfway through his roast beef sandwich when the back passenger side door of his taxi opens, and a young woman slips inside.

The rain's darkened her hair, plastered it smooth to her pale forehead and the back of her neck. She's been caught out in the sudden storm without an umbrella or coat, and her rather unflattering checkered wool jumper is soaked through and beginning to smell. Her delicate features (upturned nose, small mouth) are neither plain nor pretty, but occupy an unlikely, indeterminate space between; she's educated, employed (in medicine, probably – his cab stinks of hospital disinfectant, now, and it makes him want to gag) and suffers from mild social awkwardness. She owns at least one cat.

Jefferson Hope sees all this in his rear view mirror, in the time it takes her to close the taxi door. She bores him already.

"Sorry, darling," he says, and uses a napkin to wipe the mustard from his chin. "I'm engaged at present."

The woman pushes a strand of wet hair from her eyes. "Oh," she says with an anxious, apologetic twitch of her fingers. "I didn't realise."

"It's all right. You can sit for a moment, if you like. Dry off a bit."

She smiles, and it tips the scale toward pretty. "Thank you, Mr. Hope. I promise I won't be long."

He turns at that, shifting in his seat just in time to see her pull a dry manila folder from beneath the bulk of her jumper. She opens it, and he sees the words Hope, Jefferson H., cerebral aneurysm written on the front in small, neat handwriting.

"You shouldn't have that," Hope says, and it's as if he's suddenly awake for the first time in months. The world sharpens, and he grins. "I'm fairly sure that sort of thing is confidential."

"I'm fairly sure you're right," the woman says. She takes a photo from the folder and passes it to him; it's a date-stamped CT scan from his final visit to the hospital. He stares at the aneurysm, at the small shadow it casts across his mind, and the woman leans forward, her elbows resting on her knees. "Do you think, Mr. Hope, that people underestimate you because you drive a taxi for a living?"

He meets her eyes and sees the stillness there. The patience. Rain rings against the taxi roof. "The thought's occurred to me."

She looks down at the file folder, and her wet hair slides over her shoulder. "It's an incredible act of trust, isn't it? Getting in a car with a stranger. Putting your safety in their hands. But we don't think twice about it, not if the stranger's a cabbie." She looks up, her eyes bright. "Is that trust? Or do we just forget to fear the people we don't see?"

His fists clench; the CT scan crinkles in his hand. "Who are you?"

"I think people have always underestimated you, Mr. Hope. Your family, your employers, your ex-wife. I think you have something to prove." She takes another photo from the file folder; it's a picture of his children, laughing at the camera. The woman smiles, and looks a little like a child herself. "You must miss them."

He snaps the photo from her hand. "If you're threatening my children—"

She sits back, genuine hurt in her eyes. "I would never." She pauses. "Well, I would, but usually I send someone else when there's threatening to be done. It's important to delegate these things." She lifts her shoulders in a sweet little shrug. "And for some reason, people just don't find me very frightening."

His hand twitches toward the false gun beneath his seat. "Who do you work for?"

"Oh, I'm self-employed. Family business. You might not have heard of us; we rarely advertise." She closes the file folder and lowers it to her lap. Taps her fingers against her knees. "Do you like puzzles, Mr. Hope?"

He looks at the woman again, looks properly (upturned nose, small mouth, and eyes like the edge of a knife, carefully honed) and this time he sees. A slow grin twists across his face. "I've always enjoyed a good mystery, Ms. Moriarty."

"Excellent," says the most dangerous criminal in London, her smile sweet as sunshine. "How would you like to be one?"

Molly moves to London for university. Jim follows her.

Their first flat is an airless one-room in Whitechapel with a mildewed bath the size of a cupboard and a temperamental furnace. The once white walls are aged grey with old smoke, and their small fridge moans in the night, rattling its chains like the ghost of a man long-damned.

They've never been so happy.

In the evenings Molly takes her books with her to bed, curls into a tight cocoon of blankets and spare towels and studies by the light of a torch, sheltered from the worst of the unforgiving winter chill. At night the windows grow pale with frost, and she slips into sleep without noticing, dreaming of open textbooks and unsolvable equations and page after page of cramped, shakily written notes.

It's near dawn when the bed dips under his weight. "Budge up," Jim says, and she hears her microbio text hit the floor with a thick thud. "You're hogging the bed."

"'s my bed," she mutters, her lips numb with cold and sleep. She pries one arm free from her cocoon and points to the other side of the room. "Yours is there. Go."

"Too cold," he says, his fingers at her back, unwinding blankets and spare towels and exposing her to the air, piece by piece. Then he curls around her, chest against her shoulder blades, knees tucked behind hers, and he's so cold that she shrieks a little, into her pillow. "Oh, baby," he purrs, and makes a silly, pseudo-sexy snuffling sound into her hair. "You're on fire."

She jabs an elbow back into his ribs, and he grunts. "You smell like a sewer," she says. "Where've you been?"

"In the sewers." He wriggles against her, struggling out of his jumper and his damp-hemmed trousers. She hears them hit the floor on the other side of the bed, and the smell recedes. "You'd be proud of me, Mol. I'm making so many new friends."

Molly sighs; Jim's definition of friend has always been flexible. She pulls the blankets over their heads, shutting out the chill and the faint dawn light from the windows, and tugs at his arm until it curves around her waist, heavy and solid as ice. His breath is hot against her neck; the rest of him burns with cold, and she shudders as he shakes, his fingers trembling in hers.

Slowly, he warms against her. The sun rises, and the room grows bright.

"Jim," she murmurs, the rough weave of a blanket across her lips, "I have a class at ten."

He kisses her ear, sleepily. "Very studious of you."

"If you turn off my alarm—"

"I won't," he says, and slides his hand under her shirt, spreading his fingers wide across her stomach. "Not unless you ask me to."

His palm is warm and dry, and she leans into the pressure. Smiles. "You think you can convince me to stay in bed all day and be your hot water bottle."

"I don't need to convince you," he says. "My appeal speaks for itself."

She rolls into him, onto her other side, and his hand slips to the curve of her back. She faces him across the sleep-warm pillow, sees the shadows like bruises under his eyes and the bloodless press of his lips. He wasn't lying about the sewers; the smell is recent but not overpowering, sewage diluted with water diluted with – she sniffs – fresh soil, probably from landscaping, most likely in a public park. He fell in the dirt, smeared some on the back of his neck with his fingers, just after taking a punch – no, a shove, his knuckles are intact and Jim never misses an opportunity to hit back. Someone pushing him away, then. Someone trying to escape.

He gives her wide, delighted grin. "Reading my mind, little mouse?"

"Oh, fuck off." She tucks her head beneath his chin and sighs. "Just this once," she says. "I'll stay home just this once."

He swallows, and she watches the slow movement of his throat. His hand settles delicately on the angle of her shoulder blade, almost hesitant, easing her close. She lets her mouth brush the skin over his pulse, and his grip tightens. "I knew you would," he says, softly. "I knew it."

Molly listens as his breathing slows, gentling into unconsciousness. She watches his face, unnerved by his stillness. By the illusion of innocence that comes with sleep.

At half ten she slips out of bed to put the kettle on, crossing the arctic floorboards in a series of little, half-wincing hops. The fridge moans, and she gives it a sympathetic pat before opening the door and reaching for the milk.

Empty, of course.

She slips on socks and shoes, a clean jumper from Jim's laundry and his heaviest coat. She leaves a note on his pillow that says, Went for milk. Back soon, and places a nailbrush and a small bottle of disinfectant on the bedside table, just in his line of sight. He'd scrubbed his hands clean, but left traces of the woman's blood caked black under his fingernails; he'll need the brush to get it all.

She thinks of it as an invitation, sometimes, or a dare. Look at me, he says with every clumsily hidden cruelty. Look at what I've done.

Don't you think you could do better?

Her second winter at university, Molly goes back to Brighton for Christmas hols. Jim does not.

"I really don't understand your brother," Gran says, tapping her finger critically against the glass door of the oven. The roasting turkey glows golden in the light, and she frowns. "Imagine, being away from your only family at Christmas. Where did you say he was?"

"The last postcard was from Chongqing," Molly says from the dining room.

Her grandmother leans through the open kitchen door, her eyebrows raised.

Molly sighs. "He's in China, Gran. He's travelling. Finding himself." She sets the plates on the pristine white tablecloth with rather more force than necessary. "He'll come home when he's ready."

First Dublin, then New York and Chicago, Moscow and Hong Kong. He'd bought the most recent postcard at the gift shop at the Chongqing Zoo: a photograph of two pandas curled around each other in the branches of a tree. They were either deep in the throes of genuine panda affection or viciously trying to shove one another to the ground; it was difficult to say which.

Molly Mouse, my love, the other side of the postcard had read in his long, looped handwriting, how I miss your darling face. I am meeting lots of interesting people and learning loads, and as promised am on my very best behaviour – you wouldn't recognise me, Mol, I've been such an angel. I'm almost as good as you.

And then he'd signed it as he'd signed every postcard for the last four months: You should have come with me. Yours always, JM.

"It must be very difficult for you," Gran says later, during dessert. "Being without him."

Molly frowns into her coffee. Before Jim's little jaunt around the world, the longest time they'd spent apart was a five-day school trip she'd taken to Glasgow when they were fourteen. They'd endured that separation with little fuss, though they'd spent the evening of her return shut away in her room, sitting side by side on her bed with their backs against the headboard, each simply breathing in the other's silence.

Never again, Jim had finally said, just before the moon rose over the houses beyond, and she'd silently agreed.

It isn't quite like losing an arm or a leg, she thinks – nothing so dramatic. Her heart beats as usual (sixty times per minute, give or take), and she sleeps and eats and studies as she always has. Her concentration hasn't suffered, nor has her mood. She is herself, as always, only now she is alone.

It's bearable, but only just.

"I've been all right," Molly says. She takes a bite of her dessert, then gives her fork a meditative lick. "Though I have to do all the washing up myself, now, and he's a much better cook than I am."

Her grandmother fixes her with an unusually shrewd look. "Molly, my dear, do you think me simple?"

Molly blinks. "Of course not, Gran."

"Then please don't speak to me as if you do." Gran drops her neatly folded napkin beside her plate and pushes back her chair. "I have another gift for you. I had planned to wait another year, but I think perhaps tonight is the best time." She leaves the dining room, Molly staring after her in mute confusion. She returns a minute later and sets a small package wrapped in tastefully subdued red and green paper beside Molly's plate.

Molly frowns at it. "Gran, I—"

"Open it," Gran says, and Molly does, slides her finger into a crease in the sharp folded paper and eases it free with a clean, unnecessary precision. Inside the paper is a white cardboard box, and inside the box is a framed photograph of her mother.

She was young when the portrait was taken, no more than nineteen, and though her hair was long and straight and sand-brown, it is Jim's face Molly sees in her mother's delicate profile, not her own. The woman in the photo has Jim's nose and Jim's mouth, his narrow chin and laughing dark eyes. Her pose is formal, her pale hands folded in her lap; Molly remembers the stiff height of her posture. The cool refinement in her smile.

"This was taken just before she left for university," Gran says, quietly. She touches the edge of the simple frame. "You and James were born little more than a year later."

"I didn't know she was so young," Molly says, her eyes still fixed on her mother's face. "I didn't even know she went to university."

Gran's hand flinches away from the frame. "Of course she did," she says, her voice stiff. "She was brilliant. Very near genius level intelligence, I'd imagine, though I never had her tested."

"Oh," Molly says. "I didn't-"

"Obviously not." Her grandmother looks away, her fingers clenched in her lap. "Your father was one of her professors. He told me once that she'd taught him nearly as much as he'd taught her." The corners of her mouth lift in a brief, humourless smile. "I suppose he thought I'd find that charming."

Molly's thumb brushes the glass over her mother's high forehead. "I don't look much like her, do I?"

Gran hesitates. "She was quiet, like you. Not shy, but – reserved. Watchful." Her lips purse. "She was an odd girl. Some found her intelligence...unsettling."

"My father didn't."

"No," her grandmother says. "I don't think he did." She looks down at her lap, and the muscles of her jaw tense briefly. "I worry about you, Molly. I worry about your brother."

"Please don't, Gran," Molly says, and leans close to kiss her cheek. She smells soft, like face powder and dessert wine. "Jim and I, we'll always take care of each other."

"Yes, I know," Gran says, and passes an aged hand over her eyes.

Molly looks again at her mother's face. At Jim's eyes and the curve of his chin. "Thank you for the gift," she says, and sets the photo carefully back into its box.

Cadavers are wonderful.

She's careful to keep her fascination (her delight) from her fellow students, to pretend that the sight of the still body on the table makes her stomach churn. This is a normal reaction, one of three socially acceptable responses she's observed and learnt to duplicate, but she needn't have bothered; no one is watching her. People so rarely do.

Today's body is a man – fifty-seven years old, Caucasian, myocardial infarction. Molly can read the story of his life in the corded muscles of his arms, the late middle age deposits of fat around his waist and thighs and the slightly swollen joints of his knuckles. His stiff, death-grey face is kind, round at the chin and cheeks, and she finds it almost impossible not to smile at him. He's lovely.

Jim understands so much about her, more than anyone else ever will, but he cannot understand this. Jim thinks people are small, futile things, tin wind-up toys built either to irritate or entertain; he does not see the beauty of their architecture, the stunning complexities in a deceptively simple system. Life requires such delicate balances of blood and breath, acid and bile, tissue and bone, and she has always seen something beautiful in its ceasing. Death is the airless silence at the end of a symphony, an absence that preserves all that came before. It holds the answer to every question she's ever asked.

"I hear if you puke on the corpse, it's an automatic fail," the girl next to her whispers, a cruel lift to the edges of her smile. Molly gulps, loud enough for the whole class to hear, and the room echoes with nervous laughter. The girl smirks, and Molly pictures her on a steel autopsy table, naked and grey beneath her knife.

One body at a time, Molly thinks, and makes the first, neat incision in the dead man's chest.

Their father dies in gaol on the 4th of March, 1997. They leave London the next morning, two changes of clothing, two toothbrushes, and a hairbrush packed together in a single worn leather suitcase. Jim carries it in his left hand; his right lingers at her elbow.

"You'll be the Professor's girl," says the prison guard at Arbour Hill, leaning forward across his desk until his long nose nearly touches the glass. "You're his very image, just as he said. Mary, isn't it?"

She swallows. "I go by Molly, usually."

"'Course you do. Lovely name." He turns to Jim, arching an eyebrow. "You her young man, then?"

"I am," Jim says, before she can disagree. His grip on her arm tightens. "I'm hers, as long as she'll have me."

"Good lad." The guard's smile fades. "You'll be here to collect the remains, I suppose." She nods, and he reaches for a stack of forms, shaking his head. "So sorry for your loss, dear. He was a clever man, your father. Very well liked. Very civilised."

"Thank you," she says, and signs and initials the forms in the proper places. Jim stands close, his shoulder against hers. "He never told us he was ill. If he had—"

"You would've visited, yeah?" The guard stamps the word RELEASED at the top of each form in red ink. "That's why he didn't tell you. Last thing the Professor wanted was for his girl to see him in this place; he made that very clear." He bends down below the desk, then reappears with a small, square cardboard box, its edges sealed with silver tape. The white label on the top says simply Arbour Hill #5839. "Here he is," the guard says. "Ready for transport."

Molly takes the box. Feels its weight shift in her hands. "Thank you," she says again. "You've been very kind."

"Not at all, dear, not at all," the guard says, and turns back to his crossword.

It takes her less than a minute to pick the lock on the kitchen door of their childhood home.

The current owner is on holiday (forgotten scraps of food mouldering on the sideboard, a week's worth of post piled beneath the letterbox) and the house is quiet, blue-dark in the fading evening light. Jim follows her inside, their old suitcase in one hand and the box of ashes in the other. They move through the house like ghosts.

She marks the changes silently, knowing that he does the same. The kitchen floor's been replaced, of course, but years ago – it's stained and chipped, cheap tile worn down by a decade of use. The cabinets have been repainted (a sickly avocado green, to hide the blood) but the other changes are little more than the simple signs of age and ill repair. Her hiding place under the stairs is the same, choked with cobwebs, and the loose floorboard in the front hall creaks at a familiar pitch when Jim stands on it, rocking back and forth from his heels to his toes.

"I wonder," he says, "if they ever found the bodies buried in the cellar."

She slides her hand along the banister, feeling its forgotten grooves under her fingertips. She sees him step toward the light switch, and her grip tightens. "Don't. The neighbors will see."

He turns to her, his face half-shadowed in the light from the slender windows. "It'll be dark soon, Mol," he says. "What do you suggest we do instead?"

Their mother kept candle stubs and a spare book of matches in the hall cabinet; she reaches for them on instinct, and finds they're still there, slick with dust. She lights one candle and shoves the others into Jim's coat pockets. The flame burns high, casting tall shadows; she shields it with her hand. "Let's find a place to sleep," she says, and together they climb the narrow staircase.

There are no children in this house. Their old rooms have been turned to storage, piled high with boxes and the misshapen silhouettes of broken furniture. Her fingers linger on the linen cupboard door as they pass, the corridor close around them and shuddering with candlelight. At its end they reach the master bedroom, a large, low-ceilinged room with shuttered windows, an unfamiliar armoire, and the dark wood bed their parents shared for more than a decade.

Jim toes off his shoes and sets their case down on the threadbare rug. "Sleep or food?"

Molly sits on the edge of the bed and slowly removes her boots, her fingers stiff with exhaustion and damp. "Food, I think. If you're hungry."

He takes another white wax candle stub from his coat pocket, bends close and lights it with hers. "I'll see if there's anything salvageable in the pantry. He seems like a stale cracker and tinned soup man to me."

She slides back against the headboard of the bed and sets her candle on the nightstand, balanced in a frosted glass ashtray. "Kippers on toast, more like."

"We'll see." He pauses in the doorway, as if he's about to say more. The candle flame shudders under his breath, and he pins her with a steady, studying gaze, his eyes sharp with something like concern.

"I'm fine," she says, biting back her sudden irritation. "Go. Bring back food."

"Bossy," he says, and fades into the liquid dark of the corridor.

She watches the box of ashes, the small square shadow of cardboard and tape at the end of the bed. My father fits in that box, she thinks, inanely. He must have lost weight.

Jim comes back ten minutes later with a green apple, a box of crackers, and a crumbling block of good cheddar. "You were right about the kippers. Luckily our neighbors have cheap locks and commendable taste in cheeses." He jumps onto the bed and sets the food between them. "Behold the feast."

"Drinks?"

He pulls a bottle of beer from his coat pocket and offers it to her with a flourish. "House specialty."

She gives him a thin smile. "Such a good provider."

"Well, I'm a family man. It's how I was raised." He strips off his rain-damp coat and muddy socks, lets them fall to the floor with a wet slap. He crawls across the bed and sits beside her, his back against the headboard, his toes bare and pale against the blankets. Their shoulders touch. "Darling Molly."

"Darling Jim." She holds out her hand. "Knife."

He pulls the flick knife from his trouser pocket and drops it into her open palm. "Careful," he says, winking. "It's sharp."

She opens the beer, takes a long drink, and presses it to his waiting hand. She slices the apple in half, then into quarters. They eat in silence, passing the beer between them. The candlelight flickers.

"It was a bit odd," she says, brushing the crumbs from her lap. "That guard knowing everything about me and nothing about you."

Jim has a sliver of apple skin trapped between his teeth; she watches as he worries at it with his tongue. "Odd that our father would avoid mentioning me to the police? Or odd that he'd talk about us at all?"

She closes his knife and slides it into her own pocket. "He knew, then. About your interests."

"And yours." His gaze settles on the cardboard box at the end of the bed, his eyes dark. "I saw him before I went to New York two years ago. I applied for the visit with a false name, so he wouldn't refuse to see me."

She'd thought of that. She just hadn't tried it. "What did he say?"

"He asked about you." He finishes the beer and gives her the empty bottle, licking his lips. "I told him about Barts. He was pleased."

She turns away. Sets the bottle down beside the ashtray, a clink of glass against glass. "He was disappointed."

"You're wrong," he says, and his voice has a whip-sharp sting to it, an edge of unfocussed anger that makes her shoulders hunch and her throat ache. "Maybe he thought you could do more, Mol, that you were made for better, but he never—"

She slides clumsily off the bed, knocking her knee against the nightstand. She almost falls, but Jim's sudden grip on her waist steadies her, restores her balance. She smacks his hands away.

"Molly—"

"I'm going to use the loo. If a few minutes separation is too much for you to bear, you're welcome to stand outside the door and listen while I piss." She snatches the candle from the table and walks out of the room, down the corridor. Melted wax spills hot over her fingers, and she slams the bathroom door behind her, hissing in pain.

"Shit," she whispers, bending over the sink and turning on the cold tap. She hears Jim's footsteps outside the door; she kicks out and slams her bare foot hard against the wood, startling him away. "Leave me alone."

"You said I could listen."

Her reflection in the wide antique mirror above the sink is distorted, silvered and pale. She clenches and unclenches her fist beneath the stream of water, feeling the cold in the joints of her fingers, the fine hairs beyond her wrist. She shuts off the tap. "I'm not going to leave school."

"I didn't say you should." The closed door creaks; she hears him lean against the wood, his shoulder to the frame, his head bent toward hers. "I could do this without you, Molly. I just don't want to."

Her reflection in the mirror is blank, expressionless. She closes her eyes, and the shape of her face follows her into the darkness, the curves of skin over bone and the shadows of her eyes. Her face, and her father's. "Do what?" she asks.

There's silence from the other side, then the soft rustle of paper. Jim crouches low and slips a creased brown paper bag under the door.

The creases are deep, worn stiff and frayed with time; water damage and the lingering specks of lint suggest that he keeps it in his pocket, folded tight. Her thumb brushes a long-dried smudge of ink, and she reads the blurred remnants of her own childishly precise handwriting.

Moriarty, it says. Moriarty, Moriarty, Moriarty.

Molly looks up and sees her reflection – sees her face, and the slow twist of her father's smile.

When they are children, Moriarty is a game. A story they tell only to each other, in whispers. In the narrowing spaces between them.

The Moriartys aren't like other people, Jim says, murmuring in her ear as they slip through the crowded corridors of their Brighton comprehensive. The Moriartys aren't like anyone, and there's no one like them. Not anywhere, not in the whole wide world.

The Moriartys are clever, Molly says as she holds a tea towel full of ice to the darkening bruise high on Jim's cheek. People call them freaks, but only because they're frightened. Because deep in the lizard parts of their little, limited minds they know what the Moriartys can do.

The Moriartys don't need anyone but each other, Jim says, her fingers pinched between his as they watch the machine lower Carl's casket into open ground. The world could burn around them, and they wouldn't care.

Not so long as they got to light the first fire, she says, and he hides his smile in the long swing of her hair.

It's the tenth hour of a twelve-hour shift, and Molly slumps forward in the stiff-backed break room chair, her head in her hands, her mouth dry with exhaustion. She breathes carefully, through her nose, and ignores the harsh smell of soap and disinfectant. The cloying sweetness of the smell beneath that.

The florescent hospital lights overhead flicker once before they go dark.

"Oh, hell," she says to the empty room, and a second later Molly Hooper's pink-jeweled mobile starts singing, a tinny voice muffled by the thick felt of the bag at Molly's feet. She reaches for it blindly, fingers fumbling through pockets.

You walked into the party, her mobile sings, like you were walking onto a yacht—

She finds the mobile and flicks it open. "You know you shouldn't phone me at this number," she says, mumbles around the sharp, sour taste in her mouth. "It isn't secure."

"Darling," Jim coos, "you sound tired. Bit overworked, are we? Or are you simply pining in my absence?"

"I don't pine," she says, and she can hear his self-satisfied smile, oceans and satellites away. She scowls at the scuff marks on her trainers, at their white canvas turned grey in the half-light from the corridor outside. "Are you still in Tokyo, then?"

"Moscow. Ran into some old friends, decided to take a few days to catch up. I'll be back in the loving, mildewed arms of Mother England by week's end."

She rubs a hand over her eyes; he's run into trouble. "Anything I should know about?"

"It's personal," he says. "Not business."

As if that makes her worry any less. "Fine," she says. "I suppose your friends will know how to contact me if they want ransom money."

"It wounds me, Mol, that you think so little of my social skills."

She snorts. "And you can tell your Mr. Kozlov that I won't take kindly to receiving your severed fingers in the post; if he wants to chop you into bits, he can dispose of them himself."

"Oh, clever girl," he murmurs, pleased that she's surprised him. "Would you still love me, Molly, if I didn't have any fingers?"

She turns to the nearest hospital security camera and makes a rude gesture; he chuckles, dry and low and deceptively pleasant. "You creeper," she says, fighting a smile. "Stop spying on me."

"I can't. You're riveting." She hears the gentle, familiar sounds of his fingers tapping over a computer keyboard, and the camera bolted to the ceiling turns, capturing her from a new angle. "Though here's a question: Since we went through all the trouble of crafting a new identity for you, why didn't we give her a decent sense of style?"

She glares at the camera. "I like this jumper. It's cheerful."

"That had better be Molly bloody Hooper speaking. I may have to disown you, otherwise."

"Not if I disown you first." She slides down in her chair, hard plastic sharp against her shoulders. Her heels skid across the floor. "So. I decided to accept the Levent account."

He groans. "Dull."

"Not every job can be a rooftop assassination of a member of the House of Lords, Jim. We do have bills to pay."

"It was a close range poison dart," Jim says peevishly, "and you know it."

"If you're going to be a baby about it, I'll run the job by myself. I should be able to manage it without any face-to-face." She gives the camera a wide-eyed, openly manipulative look. "Though it is your favourite time of year in Istanbul."

It's always a risk, pushing him like this. As well as she knows him, Jim's mind remains a remote, labyrinthine thing, broken in beautiful, often arbitrary ways, and she can never predict his reactions with any real certainty. She never knows what he'll do when she pushes too far.

It may be one of her favourite things about him.

She waits in expectant silence until he sighs into her ear. The connection crackles. "I suppose I could make a small detour on my way home. If I must."

"You're a star. I'll send you the details after my shift." She reaches up and tugs at the limp length of her ponytail. Rubs the grit of exhaustion from her eyes. "I have to get back. How do I look?"

"Like the Angel of Death in pink knit."

"Just your type, then." She gives the security camera a little wave. "Say goodnight, dear."

"Goodnight, dear," Jim repeats, obedient, the edge of a smile in his voice. She's about to snap her mobile shut when he says in a sweet, high sing-song, "You know, Molly darling, I've been gone for nearly a fortnight and you haven't told me once that you miss me."

She stills in her seat. Her fingers are clenched around the armrest; she relaxes them, deliberately. "I do miss you," she says, her voice steady. "Of course I do."

"You didn't say it."

"I didn't know I needed to." She closes her eyes. The camera is still fixed on her face. "Jim—"

"A man likes to hear these things. He likes to know he's appreciated." His voice lowers. "Do you appreciate me, Molly?"

"I'm not playing this game with you," she says, through her teeth. "If you want to frighten someone—"

"But I don't want someone, Molly my love. I want you." He hums low into her ear, the sound intimate and undeniably physical, and she flinches.

It's a small enough tell, but she knows he's seen it. He laughs, and her fingers curl into fists.

"Seems you are playing my game after all," he says, and the line goes dead.

The break room lights blink on a moment later; she sits alone under their glare.

For two weeks after Jim pushes her down the stairs, Molly flinches every time he touches her.

She tries not to, she really does, but when she closes her eyes she can still feel herself falling, can hear the sickening pop of her shoulder and the sharp, sudden collision of foot-worn wood and bone. She'd be happy to forget what he did; her body won't let her.

"Stop it," he hisses when she recoils, when her hand jerks away from his. She can see the poorly hidden hurt in his eyes. In the petulant twist of his mouth. "If you don't stop, Molly, I'll make you stop."

"You stop," she says, though she doesn't mean it. (No one has ever asked Jim to change; it seems absurd to pretend that he could.) So she flinches and he fumes and two weeks after the doctors send her teetering home on a pair of crutches, Jim shoves her into the linen cupboard and locks the door with a stolen key.

"Now you can't run away from me," he says, his cheek pressed to the other side of the door. "You have to stay right here until I decide to let you go." His voice breaks, and if he were any other boy, she'd think he was about to cry. She knows he isn't.

Her leg aches and their mother is out and he could keep her locked away for hours, until the sun sets and their father comes home. The cupboard smells like dead air, like old soap and mouse droppings. Her eyes sting. "Jim," she says, "you're going to let me out of here."

"I'm not."

"You are. Do you want to know why?"

There's a silence. "Why?"

She takes a deep, dust-cold breath. "Because if you don't, I'm never going to forget it."

"Good," he says, and she listens as his footsteps fade down the corridor. As his heels clip the edge of each stair.

Jim keeps her locked in the cupboard for seven hours, without food or water or room enough to ease the weight off her fractured leg. Molly has survived longer stretches in close, dark places, has delighted in long days spent hiding in crawl spaces and beneath stairs, but she has never been trapped before. It's the helplessness that she'll remember, not the pain, and when she slips a paralytic toxin into his orange juice four months later she'll have to fight the satisfied tilt to her smile.

Jim unlocks the door after the seventh hour, opens it wide and reaches for her hands. Laces their fingers together, ready to bear her weight as she falls.

She lets him.

She likes being Molly Hooper.

Jim doesn't believe her, but it's true – Dr. Molly Hooper has a neat, rose-coloured little life, a job and a flat and a carton of mint chocolate chip in her freezer, a panacea for all the small disappointments of a day lived quietly, alone. Her parents left her behind for Australia nine years ago, after they retired (a chemist and a bank teller, both eager bird-watchers and vicious players of bridge) and she doesn't make friends easily. She doesn't really try.

Her flat is small, a third floor one-bedroom swallowed by overstuffed bookshelves, but she keeps it warm, well-lit and cozy. She doesn't have much money to spend on impractical things, but she buys cheap paintings to hang on the white walls (flowers, mostly, and one of the sea) and a few pink-tasseled pillows for the sofa.

Molly likes pink. She never really knew that about herself, before.

She wears practical, often unflattering clothes, things Dr. Hooper might have owned for years, if she'd ever existed – soft jumpers and blouses with feminine touches at the collars and sleeves, shapeless skirts that fall unfashionably below the knee. It's another way to hide, to disappear, and she finds herself grateful. Content.

Jim Moriarty looks almost comically out of place in Molly Hooper's cluttered little flat, like a character from a play who's wandered onto the wrong stage. The crisp lines of his bespoke suits seem alien in her soft-hued, secondhand world, and it bothers them both, though they don't say it aloud. Instead they sit close when he visits, heads bowed together over contracts and ledgers and long rolls of stolen blueprints, elbows sharp against the other's side. They eat takeaway dinners from soggy cartons and wipe their mouths with each other's sleeves.

Jim lives everywhere, and nowhere. He sleeps in hotels, in elegant, impersonal rooms all over the city, or sprawled across her sagging sofa, his hands curled under his chin like a boy's. Sometimes he doesn't sleep at all, and she wakes in the middle of the night to see him sitting on the edge of her bed, silently watching the shift of shadows across the bedroom wall.

He comes and goes with little warning, though she's never given him a key. He'd probably be insulted if she did.

On the morning of their grandmother's funeral he appears unannounced, leaning against the frame of her bedroom door with his hands in his pockets. She's half-dressed, the contents of her wardrobe scattered across the bed and the floor in sad, desultory piles.

"Please," he says, "please tell me this means we're buying you new clothes."

"Black shirt," she says, rummaging through the debris, the strap of her bra slipping over her shoulder. "I can't find one."

"Maybe you don't own one."

She looks up at him, frowning. "Don't be stupid. Everyone owns a black shirt." She tosses a pile of clothes at his feet. "Help me look. My train leaves in forty minutes."

He steps over the clothes and sits at the end of her bed. "You're going to miss it."

"I'm not." She pulls a white blouse from a twisted wire hanger and holds it up to her chest, the hem brushing the waistband of her straight black skirt. "What about this?"

"Absolutely not. You'll look like a waitress."

"As long as I look like someone who isn't naked, I really don't care." She drops the shirt to the floor and collapses beside him on the bed, her head falling back against the duvet. He gives her knee an absent-minded pat, and she sighs. "I didn't think I'd see you today," she says.

"I forgot. I was going to try to drag you to lunch at Claridge's."

Jim's a very good liar; if she hadn't spent most of her life listening to him lie to everyone they've ever met, she'd probably never notice when he did it to her. She nudges his leg with a nylon-covered foot. "You can still come, you know. If you want to."

"I don't," he says. "Why do you?"

She sits up beside him, her arms wrapped around her bare stomach, her shoulders rolled forward. "I don't know. One of us should be there."

"Why? To keep up appearances? To seem normal?"

"Maybe, yeah." She shrugs, annoyed. "People might remember us. They might notice if we're not there."

"All her friends are dead, Molly. Dead or mindless, drooling meat bags long past their use by date. Don't pretend this is about security."

"I'm not pretending anything. I'm just trying to get dressed." She stands, reaching for the nearest pile of clothes. "I have a purple shirt. Purple is sort of like black, isn't it?"

"Molly," he says, and she stops. Folds her arms across her chest and shivers a little, the chill in the room touching her bare skin for the first time.

Gran had slipped into senility in the last years of her life, become a mindless, drooling meat bag in a hospital built to look like a home. Molly never visited her there; she isn't her granddaughter anymore. All records of her old life have been destroyed with the Moriartys' usual ruthless precision, and if in a rare moment of lucidity Gran had asked for her grandchildren, had called for Jim or for Molly, a kind nurse with calloused hands would have pressed her shoulder and said no dear, you remember – your Lizzie never had little ones. You know that.

Or maybe she never thought of them at all. Maybe she wanted to forget.

"Oh, fine," Jim says, standing and stripping off his suit coat. "Anything to get that sickeningly maudlin expression off your face." His shirt is ash grey silk and probably cost as much as Molly Hooper earns in a month; he unbuttons it with an almost brutal efficiency, his mouth a thin line.

"Jim—"

He unbuttons the cuffs and slides the shirt off his shoulders. "Shut up. You're going to miss your train." He slips her arms through the sleeves, steps close and works the buttons, starting at her waist. "If you stain this, you're buying me two to replace it."

She grins up at him. "Literally giving me the shirt off your back. You big softie."

He gives the skin over her collarbone a sharp pinch, and she squeaks, slapping his hand away. He stands back, watching as she buttons the shirt to her throat. When she's done, he reaches over and slips the top button from its hole with a flick of his thumb. "The fit isn't ideal, but it'll do. I assume you've a cardigan or something equally absurd to wear over it?"

The muted silk is still warm from his skin, ever-so-slightly damp with sweat beneath the arms and at the back of her neck. It smells like his soap. "I have a cardigan; I think it landed behind the chair," she says, and he rolls his eyes.

"Of course it did." He ducks behind the ratty old armchair in the corner, and she watches the lean line of his back, the pale, sunless skin of his naked shoulders. He'd freckled when they were small, freckled and burned red even under cloudy skies – they both had. The lobster twins, Gran had called them, and threatened to throw them into a pot.

Jim drapes the cardigan over her shoulders. "You're getting sentimental in your old age. Stop it."

"It's not sentiment." Molly looks away, twisting her arms to slip them into the sleeves of the cardigan. "It couldn't have been easy, taking us in, but she did. She loved us."

"There's a difference between love and obligation," he says, and she turns back to him, surprised. He gives her a wry smile. "Underestimating me again, Mol?"

"I don't," she begins, but he steps in close again, his hands easing over her waist, under the dark wool of the cardigan, and his smile turns hard.

"You forget, dearest, how much you look like our father. Do you really think she ever looked at you without seeing him? Ever saw your face without thinking of the man who murdered her daughter?"

Her fingers curl against his chest, ready to push away. "He didn't."

"Gran thought he did. Forensics ruled it a suicide, but you know what he was capable of. She was the centre of his world, and she ruined him." Cool fingers cup her cheek and he presses a kiss to her temple, hard enough that she can feel the edge of his teeth behind his lips. "I know more about love than you think," he says, and she's opening her mouth to answer (to breathe) when the front door buzzes.

There's a silence.

"Taxi," she says softly. "To take me to the station." She pulls away, slowly, and he lets her. His arms fall to his sides. "Thank you for the shirt."

He laughs and turns away, his hands slipping into his pockets. "Oh, anytime."

"I think you have a spare in the wardrobe if you—" The door buzzes again, and she bites her lip. "I really have to go."

"Of course." He swings his suit jacket carelessly over his bare shoulder. "Give the old cow my regards. Tell her I think of her every time I cheat a pensioner out of her life savings."

She takes a deep breath. "Jim—"

"Don't." He reaches out and gently straightens the collar of her shirt with one hand. "You'll miss your train."

The cabbie leans on the buzzer; she stumbles into her shoes, runs into the sitting room and scoops up her handbag, coat and keys. Jim watches from her bedroom door, his shoulder against the frame. She pauses at the front door and looks back at him, at the dark set of his eyes. His slowly fading smile.

And he calls me sentimental, she thinks as the door closes behind her.

She's wrist-deep in a corpse when the posh boy from the pool walks into the Barts mortuary, fixes her with that cool, inescapable stare and says, "Ah. Fresh meat."

She blinks at him, then down at the grey-faced greengrocer (sixty-two, Asian descent, suspected intracerebral hemorrhage) on her table. She looks back up, the greengrocer's left lung still in her hands. "Sorry?"

"You're new here. Started less than a week ago, judging by the laminate on your security badge." He walks up to the table, slipping off his black leather gloves and tucking them into the pocket of his coat. "I need six samples of human cardiovascular tissue from six male donors over the age of forty-five. Recent deaths would be best, of course."

They both look down at the open body cavity between them. The greengrocer's lung drips a little onto the table.

"I can wait," he says, and gives her a stiff, practiced smile. She thinks it's meant to be charming; it isn't.

He's much the same now as he was nineteen years ago; time has deepened his voice and lent his once awkward height an enviable, almost calculated grace, but when she meets his pale eyes she still sees the boy he was, his fierce dissatisfaction and his shoes that pinch. She wonders what changes he'd see in her, if any; if he'd remembered her, she might've asked.

"You're not a doctor," she manages instead, and he raises an eyebrow.

"Obviously."

"Right," she says. "Obviously." She turns away, carefully setting the greengrocer's lung on her scale. She takes a breath. "I suppose you must be Sherlock Holmes, then," she says, over her shoulder.

His smile turns thin. "Part of the Barts training seminar now, am I? I'm flattered."

She laughs, and it escapes in an awful, bird-like titter that's as self-conscious as it is inane. Embarrassment coils like a snake in her stomach, and she feels her face flush red. She looks down, stripping off her medical gloves with trembling fingers. "Right. So. You need tissue samples?"

He nods, distracted; the faint bruising between the greengrocer's toes has caught his attention. "Six of them, yes. As soon as possible."

She folds her hands in front of her and tries to look steady. Professional. "They told me I could give you whatever you need so long as you fill in the paperwork and don't take anything out of the building."

He looks up from the corpse's feet, his strange, false smile back in place. "Dr. Hooper."

"Molly."

"Molly. What a lovely name." He slips around the autopsy table, easing closer until she has to tilt back her head to meet his eyes. His smile widens. "Molly, do you know what I do?"

She nods, mesmerised. "They said you work with the police. As a sort of consultant."

"I help them catch criminals. Murderers, mostly." His gaze drops to her mouth, a blatant flirtation. "Would you like to help me, Molly?"

"I—" She hesitates. "I suppose I could fill in the forms myself, to ease things along."

His head tilts to one side. "And?"

"And I suppose, as long as no one sees you leave—"

He turns away, and in two long steps he's placed the autopsy table between them again. "I knew you'd understand. I'll be upstairs in my lab, when the samples are ready." He turns to go, but a moment later he pivots back, pointing to the greengrocer's toes. "I don't suppose you've noticed—"

"The injection site?" She laughs again, awkwardly. "I'd have to be pretty thick to miss it, wouldn't I?"

He watches her, his pale face eerily expressionless. "Self-administered?"

She frowns; if this is his idea of a test, it's not a very good one. "Of course not. Whoever injected him gripped his foot to hold him still. You saw the bruise pattern."

"Yes," he says slowly. "I did." Then he looks at her – really looks, with a relentless, scalpel-sharp precision meant to cut her open and expose the delicate systems inside. He reads her habits in the sunless skin of her face and hands, hears the quiet of her flat in the carefully mended sleeves of her secondhand jumper. He sees her and dissects her, piece by piece and part by part, observation turning to conclusion ending in summation. She watches him, the taste of anticipation sharp at the back of her throat, and waits to be revealed for what she is. To be caught.

He looks away, and the corner of his mouth ticks upward in something like genuine pleasure. "Well done, Dr. Hooper. You may be more useful than I anticipated." He turns and strides to the door. "Text when you've prepared the samples," he calls over his shoulder. "I'm just upstairs." Then the door swings closed behind him, and he's gone.

"But—" She bites her lip. But I've an open body on the table. But I don't know your number. But you were supposed to see.

The greengrocer lies open beside her, poisoned with the prick of a needle, murdered by his own wife. Or son, possibly – definitely someone he knew. Someone he trusted. She gives his ankle a sympathetic pat. "Families," she sighs. "Don't get me started."

A month later Molly's in the bath when Jim walks in and slumps bonelessly against the side of the tub. His head tips back to meet hers, crown to crown on the water-warmed porcelain. "Rachel Howells is in police custody," he says. "They found Brunton's body."

She slides lower into the water, and her knees rise above the surface like pale, pruning mountains rising from the sea. Her hair curls in the heat. "Really."

"Yes," he says, lingering on the sibilant. "Really."

She purses her lips, reluctant to ask the obvious question; Howells had been Jim's account, not hers, and they've never lost a client to police interference before. She tries to think of a less incendiary way to say So how'd you muck it up, then? and fails. "I suppose they found the money as well?"

Jim toes off one of his shoes and kicks it at the bathroom wall. It hits with an unsatisfyingly muffled thump. "Musgrave hired a private detective – some amateur with an absurd name and a website. He found the body, the money, and Howells and handed them all over to the Yard wrapped in a neat little bow." He looks over his shoulder and meets her eyes, his lips pulled back in a snarl. "I didn't make any mistakes, Molly. It was perfect."

Obviously not, Molly thinks. Her father always told her that there was no such thing as a perfect crime – only a very, very good one. Both Molly and Jim are excellent criminals; the thought that Sherlock Holmes might be better—

"Fascinating," she says, almost to herself. "I wonder how he did it."

Jim rips off his other shoe and chucks it into the sink. "Maybe I'll ask him," he says, "just before I split him open like a grape."

Molly sinks in the water until a soap bubble brushes her chin. "I think you mean a melon."

"What?"

"People don't split grapes, they split melons. At least, I think they do." She frowns. "Maybe I'm thinking of a coconut."

He twists around until they're face to face, his elbows resting on the edge of the bath as he looks down at her. Bath water seeps into the dark sleeves of his suit. "You don't want me to kill him."

"I want you to wait." She lifts one foot from the water and curls her toes around the cool steel of the tap. "He might make things interesting. For a while."

A slow grin chases the last of the anger from his eyes, replacing it with something glittering and cold. "Am I boring you, little mouse?"

"Not yet," she says. She shrugs, and soapy water surges around her shoulders. "I'll tell you if you are."

For a long, perilous moment he says nothing at all, his face unreadable. Then he laughs. Bends down and kisses the damp hair just over her ear. "Hush, you, or I'll split you like a coconut."

She flicks water at his tie. "Get out of my bathroom, pervert. I'm naked."

His eyes go ridiculously wide. "Really? I hadn't noticed." He jumps up onto his feet, socks slipping a little on the title, and does a slow moonwalk back to the open door. "What do you think? Thai or pizza?"

"Thai, definitely."

"Pizza it is." He spins out the door, half-closing it behind him before he peeks around again, his expression suddenly thoughtful. "He would have to be unusual, wouldn't he? To beat us."

"Unusual or unlucky." She grins. "Might be fun to find out which."

He rolls his eyes. "Fine. The grape-splitting is postponed." He points a well-manicured finger at her. "Just for the moment, mind you. We're definitely going to kill him; I'm simply saving it for a day when I need a bit of cheering up."

She shakes her head, hair clinging damply to her neck. "You know what they say about comfort-killing, Jim. You should really find more constructive ways to cope with your emotions."

"Like pizza?"

"With mushrooms, I think. And onions." She ducks briefly beneath the water and then rises again, wiping her eyes. "Now bugger off. I have to wash my hair."

He smirks. "I like it better dirty."

"I like you better on the other side of the door."

"Well," he drawls, "I think we both know that's not true." The door closes behind him with a neat click, and she shivers.

The water's gone cold.

A decade later, John Watson meets her eyes over a green kitchen table and says, "You know, there's something I've always wondered."

Molly takes a sip from her still-steaming mug; John's sits in front of him, untouched. A little rude, she thinks – it is difficult to drink tea with one's hands bound to a chair, but he could manage it if he tried. "You can ask me anything you like," she says. "It'll help pass the time."

The muscles of his cheek twitch – anger, probably. Maybe fear. "You could've killed Sherlock years ago, before he ever heard the name Moriarty. Why didn't you?"

She pauses, mug at her lips. Sets it down again and folds her hands in front of her, on the wood. "Because I liked him," she says, "and I didn't want him to die."

John stares at her. "And now?"

"Now it's just part of the game," she says, and drops a straw into his mug of tea.