Author's Notes: This story was inspired by that most excellent of comedies, Brooklyn Nine-Nine, except it's set in a fictional Criminal Investigation Department in a police station in London. I have done a lot of research into the inner workings of the British police force, thanks to an in-law of mine with insider knowledge, but I've still taken a few liberties to write this story. As a precursor to the action, I'll warn you all that Lily, James and their friends are in their mid-to-late twenties, so there is adult language and light-to-middling smut involved. That said, this story is a romance, and there'll be plenty of that.

You don't need to have watched Brooklyn Nine-Nine to read this. This story is also fully completed, and I will update its chapters once a week.

Circle-Jerking: My thanks and love go out to the brilliant Kristina – to whom Algernon must always be attributed, and who was enthusiastic about this idea from the very first. Happy Birthday, my dear friend! Enjoy your gift! I also want to thank Captain Mai (my Marvel super-heroine of choice) and my beloved proofreader, Lady Katie (the Sansa to my Arya), for their support and willingness to read scenes. My life would be far less magical without the three of them.

Chapter One

It is March 9th, 2015. Filthy rich, lifelong-Londoner James Potter will be twenty-seven-years-old in eighteen days, and Lily Evans, who split up from her boyfriend six months prior, lives with her father in the city of perspiring dreams. Meanwhile, a very important woman starts a very important job.

On a March morning that was cold, dry and unremarkable in every other aspect, Minerva McGonagall began her first day as Detective Chief Inspector at the age of fifty-two. It was, therefore, a remarkable day for her, and a very unlucky day for the criminals of Holborn and its surrounding areas, for Minerva – so named for the Roman goddess of wisdom, war, arts, school and commerce – was an impressive personage in all ways.

She stood as tall as most men, wore fine tailored suits and could throw a cracking right-hook when occasion called for it. Her sharp green eyes observed the world behind silver spectacles and seldom did they miss a thing. Her talent for holding a room's attention had few equals, and if her will was made of iron, her wit was sharpened steel. Most of her friends and colleagues agreed; those who didn't often labelled her - bossy, frigid, bitch, and other titles born of misogyny, but she had grown impervious to such maliciousness.

Law enforcement remained a male-dominated playground despite decades of evolution, but it never prevented Minerva from soaring, even though it slowed the progress. In the eighties, Minerva's colleagues beleaguered her with facile jokes about her sex. Some requested cups of tea, some patted her bottom, but all would be embarrassed by her superiority in the end. After thirty years on the force she had been hand-selected for this prestigious position, a long-held dream finally realised. She was, in fact, so determined to take the job that she left Cambridge - a city for which she felt an affection that could only be rivalled by her birthplace, the Scottish county of Caithness – and moved to London. She detested London, with its noise and its congestion, but she would have flown to Timbuktu for her job, so she bade goodbye to her cosy house that overlooked the river, kissed her rowdy nephews on their ruddy cheeks, and left.

Now in Holborn, on the verge of a new accomplishment, Minerva entered the Criminal Investigation Department with all the assurance of age and experience, her polished heels clicking against the floor with military rhythm.

Her kingdom was a bleak concoction of blues and greys bathed in unflattering, urine-tinged light. Due to the earliness of the hour she had expected silence, but her quiet repose was shattered by the two young men she met in the centre of the room. Amongst the vinyl-covered MDF desks, tattered swivel chairs and sticky mugs of yesterday's coffee they stood – or rather, they perched – atop two chairs, laughing uproariously as each tried to knock the other down with fat manila folders.

One of them, the taller of the two, spun wildly off course, crashed into a nearby desk and sent a stack of papers fluttering to the ground. Minerva's eyelid twitched.

It is March 10th, 2015, and Minerva McGonagall has done a fine job of settling in to her new office. Beatrice Booth, a police administrator, is twenty-eight-years-old. She is an exquisite beauty, a talented ballerina and possesses considerable psychic powers – or so she believes. James Potter will be twenty-seven-years-old in seventeen days, and Lily Evans is about to receive a phone call that will change her life forever.

"I'd like to know more about my detectives," said McGonagall.

"You're asking the right person," Beatrice Booth – named for Beatrice di Folco Portinari, the unrequited love and muse of Dante Alighieri – assured her. "I'll sit, if you don't mind."

Her new boss extended her hand across the desk to indicate that she should feel free, and so Beatrice lowered herself into the chair opposite with a straight back, and crossed one long, brown, diligently moisturised leg over the other. People often remarked that Beatrice was a model of poise and elegance, nobody more so than the lady herself. She laid her own hand upon McGonagall's desk and ran her fingers along the grain. "This desk is very lovely," she remarked with sincerity. The colour fell between rust and chocolate, and it had an unpolished finish that only added to its charm. Beatrice especially enjoyed the backdrop it presented to her slender brown hand and freshly manicured nails, painted in her preferred shade of gold. "Is it custom made?"

McGonagall nodded. "Reclaimed Douglas Fir. I found it in a small furniture shop in Tacoma on a family trip to the States, and my brother was kind enough to purchase it for me. The cost of shipping was outrageous, but he wouldn't be dissuaded."

"He sounds kinder than my brother. Or wealthier. I like it – the desk, I mean. Your office is much nicer than the stereotypical DCI setup."

"What's the stereotypical DCI setup?"

"Oh, you know, polished mahogany and a shelf full of dusty encyclopaedias? Interior design can tell you a lot about a person."

In the experience of Beatrice Booth, people presented themselves in one of two ways – who they knew they were, or who they wanted people to believe they were. McGonagall, who on the surface appeared as staid and unyielding as a frozen pond, slid easily into the former end of the scale. Her office was adorned with family photographs and trinkets from her native country; like the tartan biscuit tin, the calendar that showcased the scenery of Caithness, and the large, misshapen mug - clearly homemade - that had been painted in a childish hand, bearing the words Auntie Minnie in lurid green letters. Beatrice had known that she would like McGonagall from the very moment she clapped eyes on that mug.

"Do I detect a hint of a West Country accent?" said McGonagall.

"Somerset born and bred, I am. I come from a little town called Chard. It's very cute. Very quaint. Dull. London's my place."

"But you got your looks from another country."

"Ciertamente, my mother is Spanish, from Pamplona. She and my father live there with my little sister."

"Do you get to visit often?"

"Whenever they're willing to pay for it. Do you get back to Scotland often?"

"As often as I can." McGonagall slid her biscuit tin across her desk. "Have a biscuit. For how long have you been working here?"

Beatrice reached into the tin and removed a sugary shortbread finger. "I started almost as soon as I moved to London, so ten years. DCI Minchum was in charge then. He set me to making tea and filing paperwork, but now I basically run the office. It couldn't operate without me."

"As I see from these recommendations," said McGonagall, indicating towards a pile of papers that lay her near elbow. "I won't set you to making tea, I can assure you."

"Don't make it anyway. I'll make it for you, but the boys can get stuffed. They're capable of sustaining themselves without flooding the station."

The corners of McGonagall's lips twitched upwards.

"So," Beatrice continued, her confidence in McGonagall's approval of her growing. "What exactly do you want to know about the boys?"

"Anything that I can't learn from these files. I observed them yesterday, but new employees can be guarded. I'd rather hear about them from a person with whom they feel more comfortable."

"Then I'm your girl. They're all men, so there isn't much to any of them."

McGonagall rewarded her with a genuine smile this time, and Beatrice knew that she had been won. They had come to an understanding, she and this sharp, formidable, very serious woman – so serious that even the sleek, black knob of hair at the back of her head dared not misbehave.

In ten years, Beatrice Booth had worked beneath two DCIs, Harold Minchum and Cornelius Fudge. Both men treated her like a glorified waitress, a pretty, perambulating kettle designed to appear when summoned with a hot drink and a winning smile, tight skirt not required but preferable. Fudge, McGonagall's predecessor, a man in his sixties with three adult children, would often suggest that Beatrice, his leggy brunette, would find a nice husband if she dyed her hair blonde. Three detectives in his employ watched her feed Fudge's festive green bowler hat into a paper shredder at the previous year's Christmas shindig, and not one of them had given her up. The boys were loyal to Beatrice, and her alone.

"Tell me about Detective Constable Black," said McGonagall, studying a sheet of paper that undoubtedly held Detective Constable Black's details. "Whatever I can't learn from this."

"Sure," Beatrice agreed. She swung her chair around and pointed to her left. The wall that separated McGonagall's office from the bullpen was floor-to-ceiling glass, and Sirius Black – named for the brightest star in the night sky – was clearly visible through the open blinds, lounging idly in his chair. "So, as you'll have noticed, Sirius was unfairly blessed with old-Hollywood good looks, and he's hyper aware of it. He pretends that he isn't, but he is. That out-of-work musician look he's rocking is totally deliberate. Not my type, but there you go."

"I'm not a fan of long hair on men," said McGonagall disapprovingly. Beatrice snorted.

"Please, tell him that often. He's very good at his job, which you'll know, but he thinks he's Will Smith in a cop movie and that he's fighting the establishment from within. He got in a spot of trouble for roughhousing before he came to the CID, but nothing so serious that it ended up on his record. He's smart, though, and he's passionate about putting criminals in prison. You can't fault his dedication. If you want my advice, I'd put him on cases with DC Lupin – he doesn't take any of Black's nonsense."

"And what else can you tell me about Lupin?"

Remus Lupin – named after one of the founders of Rome by his parents, both of whom were history enthusiasts – sat at the desk adjacent to Black's. Remus was no match for Black in the looks department, but he had his own charms. His eyes were intelligent, and the prematurely grey streaks in his sandy brown hair gave him a refined, scholarly air. "You can't fault Remus, really. He's a sweetheart. I don't know what you've got on him in those files but it's worth mentioning that he's very sensible, very diligent and very consistent. The reason he handles most of our sexual assault call-ins is because he's the next best thing to a female detective. He knows how to put people at ease. People feel comfortable around him."

"I see that he's had health problems in the past?"

"That's why he gave up the regular beat and came here. A less action-packed role suits him better. You'll like him."

"You certainly seem to."

"Well, I wouldn't kick him out of bed for eating crisps, but I'm ever the professional."

She smiled over at her shoulder at McGonagall, who was completely unperturbed by this confession. "What about the others?"

"Let's see, who do we have left?" said Beatrice, and spied Peter Pettigrew – named for his father and his father before him – a portly blonde with an upturned nose, buttoning his coat. "Don't ask Pettigrew about food and especially don't ask him about restaurants, because he will start harassing you to follow his food blog, Pain au Pettigrew. Don't let him have your personal email, either. He'll spam you with links."

"Does he know what he's talking about?"

"Yes, but we don't like to encourage him. Bless him, he's committed, though. He's a hard worker and you'll never have to chase him for his paperwork. You'll be chasing DC Lockhart all the time." Gilderoy Lockhart – named for an infamous Scottish outlaw he bore no resemblance to – was next to Peter, checking his foppish mane of wavy blonde, Hugh Grant inspired hair in the back of a teaspoon. "Lockhart's alright, nothing special, never been good enough to make DS even though he's been here for donkey's years. He works mostly with Sluggy. Slughorn, I mean."

"Where is Slughorn?"

"Out getting food, I assume. He's basically checked out at this stage, leaves most of the work to the boys. You'll find that we're a very young branch. Sluggy and Lockhart are the only detectives who've been here since before I started."

"Very well," said McGonagall. She shuffled her papers, and clucked. "So, that only leaves the young gentleman who greeted me by free-falling into a desk yesterday."

"Potter's the best detective you've got," said Beatrice, with much confidence in her words, but at that very moment, James Potter – so named because his father had a stupid name and didn't wish to subject his son to bullying – hurtled by the window, lassoed to his chair with a telephone wire as he sped towards Black, or inevitable injury, at high speed. She sighed. "Although it's just like him to make himself look bad while I'm in the middle of praising him."

"That's my best detective, is it?" said McGonagall. Beatrice turned to face her. "He doesn't seem intent upon impressing that fact upon me."

"Well, he's a moron," Beatrice explained. "A moron and a great detective, the latter you'll already know because you've seen his record. Solve rates, court performance, all brilliant. He's already a Detective Sergeant and he's only twenty-six. He's even got a genius IQ, as he frequently likes to remind us."

"And you believe that?"

"Yeah, I do. Potter doesn't lie. He likes to boast, but only about things that he can back up with fact. He acts like a tit most of the time, but he is genuinely brilliant. His problem is that he's had no discipline, and he's never worked beneath a superior who didn't let him do whatever he wanted. Slughorn can't even control his own diet, let alone his team, so he's been no use at all. But Potter's fine, really. He just needs taking in hand, and he needs to be kept away from Black when he's working."

"Don't they get along? They seemed to be having a good time when I walked in here yesterday."

"Oh, yeah, they're best mates. They even live together, so they should be able to survive if you keep them apart at work."

"Well then," said McGonagall, gathering her papers together in an orderly little pile. "I owe you my gratitude, Booth. Thanks to your information, I've finally figured out what I dislike about this branch."

"Which is?"

"It's almost entirely male," she replied, with a thin crease between her arched brows. She pushed the biscuit tin back to Beatrice with one hand and picked up her telephone with the other. "And that's entirely unacceptable. Help yourself to another biscuit, I have a few calls to make."

It is March 23rd, 2015, and Minerva McGonagall has been enjoying her new position for two weeks, aided by the ever-brilliant Beatrice Booth. James Potter will be twenty-seven-years-old in four days, and has no idea that he is about to be dazzled, wholly and irrevocably. Meanwhile, Lily Evans, who we are about to meet for the first time, has spent the past fortnight overhauling her life.

When the alarm went off that morning – a cheerful, calypso tune that she had naively hoped would start her day with a smile – Lily Evans knocked over a glass of water in her haste to silence it, then stepped in the puddle when she got out of bed. Her new tights formed a gaping ladder as soon as she pulled them on and so she was forced to shave her legs, an arduous task for a half-asleep woman. She nicked a sensitive spot by her ankle and wasted precious minutes patching it up.

"Shit!" she cried when, having raced to her door in a rush, she fell over the disassembled tent that lay in the hallway, an unwanted, unused remnant of a dead relationship. "You stupid, buggering fuck!"

The tent simply lay there and refused to apologise, and as Lily was of no mind to apply logic to her feelings she kicked it before she left, her nerves in shambles. She was having an awful morning of the highest degree.

But Lily – so named for the flower her late mother had adored – couldn't afford to have an awful morning of any degree. It was her first day in her new job and her first week in an old city. Her family had left London nine years prior and Lily had not visited in five, so her once encyclopaedic knowledge of its transport system had grown rusty with misuse. As it happened, she overestimated her travel time and arrived at Holborn tube station with an hour to spare. Her right knee smarted, reminding her that she had faceplanted in her flat for nothing.

She choked down an Egg McMuffin and a blistering, flavourless cup of tea in a nearby McDonald's before she walked to the station. She stopped to check Google Maps only once, which she considered a triumph, and had regained her composure by the time she arrived. A stringy-looking uniformed officer showed her to the CID and boldly asked her to go for a drink with him later. Eyeing the shiny gold ring on his wedding finger, she refused politely and left him to go home to his unsuspecting wife.

She found Minerva McGonagall in her office.

"Good morning," she said, her voice ringing in the silence, and McGonagall sprang to her feet with the sprightliness of a much younger woman.

"I knew you'd be here early, Evans," she said, and held out her hand. "Welcome. I trust you found the place easily?"

A well-worn novel – The Handmaid's Tale – lay bookmarked on McGonagall's desk, next to a steaming mug of tea. She'd been having one of her human moments, a term that Lily had coined but never dared speak aloud. In Cambridge, McGonagall's presence at the station was omnipotent, so much so that it was difficult to picture her in everyday situations. She was to Lily what Jo March had been to her as a child, a heroine, an idealised version of the person she wanted to be. Lily could recall the day they met in a Waitrose, and how inelegantly shocked she was to see McGonagall in the real world, the same feeling she'd experienced years earlier when she and her mates bumped into their French teacher at Alton Towers and realised that he had a life outside of masculine and feminine nouns.

Sometimes, it was easier to believe that McGonagall simply vanished in a puff of smoke o' nights and reappeared in an otherworldly realm that regular, unremarkable people had no hope of entering. Lily had always wanted to be remarkable and she had especially wanted to be a heroine, an ambition she struggled with until she moved to Cambridge and decided to follow in her father's footsteps by joining the police.

She rushed to take McGonagall's hand, beaming like an overeager Miss Universe contestant. "I did. Thank you so much, sir… for the opportunity. I'm so excited to be here. Thank you – again."

"Please, sit," said McGonagall, and moved to her office door. "Have a biscuit. I'll just get you a cup of tea. Milk and sweetener, as I recall?"

Lily nodded, momentarily overjoyed by the knowledge that the woman she hero-worshipped knew how she took her tea and was actively engaged in making it for her, and McGonagall swept from the room. She sat down, noticing as she did that the calendar she had bought McGonagall for Christmas was hanging proudly on the wall. She reminded herself to refrain from demonstrating her pleasure in a manner that would be considered rude when McGonagall returned, such as pointing it out, or bursting into tears.

Lily had been the same – always looking up to some feminist icon – since her childhood. Her mother was the first, followed by a plethora of fictional allies and their creators, and finally McGonagall, who taught her to become her own icon. It was a lesson that Lily tried and succeeded to live by, although she couldn't quite get over the passionate attachment she felt to her mentor. Her decision to leave Cambridge and join McGonagall in London had been lightning-quick and excitable. "Yes!" she had squealed down the telephone before McGonagall could finish the question, and what followed was an unexpectedly smooth transition. She emptied her savings, found a very nice flat in Colindale, purchased half of IKEA and started her new life, just her and her tuxedo cat, with little fuss.

Naturally, she believed a catastrophe was imminent. Perhaps McGonagall had hired her by mistake. Perhaps she had asked Lily to come as a guest, not an employee, and now felt too awkward to reveal the truth. Perhaps her landlord would reveal himself as the leader of a drug cartel and her flat concealed crucial evidence, for everything had gone too smoothly to be allowable and Lily was certain that she wouldn't feel comfortable until some disaster fell into her lap.

McGonagall entered the office with her tea, and bade her once more to take a biscuit, which Lily did. Her on-the-fly breakfast hadn't been particularly satisfying.

"So," said McGonagall, returning to her seat. "How was the big move?"

"It was good." She hastily swallowed a mouthful of shortbread. "I moved in yesterday, Dad and one of his mates drove me down in the van."

"And how's the flat?"

"Oh, it's lovely. Thank you so much for recommending it."

"Oh, don't thank me, thank Booth when she comes in. She's the one who found it. Have you unpacked?"

"Nearly, I just have a little bit left to do."

Lily had done nothing, in truth, but collapse into bed the night before. Her new living room was overflowing with boxes and the boxes were overflowing with clothes, books, crockery and things that Petunia insisted she would need. Her elder sister – the ultimate consumer – was a routine buyer of expensive kitchen gadgets and complicated exercise machines. She was the type who kept fine china for special occasions, but for whom no occasion was special enough.

To celebrate Lily's move, she gifted her with a sewing machine and a bread maker. Lily didn't sew, and she bought her bread from the shops for 90p like a regular person. Petunia, who lived in a neat, detached house with her bulbous husband, liked to talk of loft conversions, patio furnishings and other things that Lily didn't have. It seemed to give her great satisfaction.

"I hope the suddenness of my request didn't put you through any trouble."

"No, not at all. There was nothing keeping me in Cambridge, aside from Dad and some mates, and it's only sixty miles away on the train."

"Are you looking forward to reconnecting with all of your old friends?"

"Well…" Most of her friends at school had drifted away from her after she left London, excepting Mary MacDonald, and Lily had unintentionally ruined her relationship with the only other person who was worth a damn. "Actually, my friend Mary's moving back here in August. She's been in Australia for five years, so that'll be nice."

"Good, well, I hope you settle in quickly. I have to say, I'm delighted that you chose to join us."

Lily coloured. "Are you really?"

"Yes, of course. Does that surprise you?"

"To be honest, I assumed that you'd ask someone older and more experienced, if you were going to ask anyone at all. Jorkins was a little upset that you didn't ask her."

"Oh, I don't give a toss about Bertha Jorkins, that odious gossip," said McGonagall. "You may be young, Evans, but you're the best detective I've worked with in a very long time."

"I – thank you. That's very kind."

"It's not kindness, it's truth. The team should come in soon. They're aware that we have a new DS starting today so I expect everyone to arrive early."

"I'm looking forward to meeting them."

"You say that now," McGonagall sighed. "Reserve your judgement for when you meet your partner. He's a bit of a handful."

"Oh?"

"I should warn you about him before you get to work," said McGonagall, leaning forward on her elbows. "He's good at his job – very good – but he's a damned fool. He pulls pranks on his colleagues and arranges silly games for the office to participate in when he should be engaging his talents more productively. Last week, he had the whole bullpen – including a witness and the cleaning lady – standing on the desks and pretending the floor was lava. The week before that, I went twelve rounds with him because he refuses to wear a tie. I've even caught him playing with action figures at his desk."

Lily liked the sound of him immediately. She arranged her features into a look of disapproval. "How childish."

"Yes," McGonagall agreed. "You can only imagine the trouble I've had with him, Evans. I want this branch to be the best in London, which means I need him to pull his socks up and really apply himself, so here's what I propose – you partner him for a trial period of six months, working on cases as co-primaries. Everyone else in this office encourages his behaviour but I know you, and I know you'll be able to handle him. When the six months are up, you'll have your pick of the bullpen."

Lily turned this idea over in her head, shifting uncomfortably. "So, essentially, I'll be on babysitting duty?"

"No. No, the reason I'm partnering the two of you is to provide him with an example of how an exceptional DS ought to behave. No babysitting involved. I think you'll be a good influence. He's your age and he's shown no resistance to working with women." Like some, she might have added. Lily had experienced enough in-office sexism to read between the lines.

"You're sure?"

"He seems like a sweet boy."

"But you say he acts out?"

"In silly, time-consuming ways, but there isn't a spark of malice in him."

"Well, then." Lily shrugged. "I've dealt with unruly boys before. Why not?"

"Excellent. That's settled. I imagine the team should be here soon. Booth will show you around, and then we can get you to work immediately. I've set up a desk for you next to Po—what on earth are they doing?"

Of all the potential surprises that Lily could have expected on her first day at a new job, she did not expect to hear Coolio's Gangsta's Paradise blast through the air with the sudden intensity of cannon fire, but that was exactly what happened. She jumped; McGonagall had already risen to her feet, nostrils flaring, but otherwise showing no sign of shock. "Those fools," she hissed, and swept to her office door. "I'll be back in a moment, stay here."

She left, the door banging shut behind her, and Lily, who had swung her chair around to locate the source of the upset, rose from her seat and went to the window. McGonagall's blinds were closed, so Lily had to poke her finger through a gap and peep through to see what was happening.

A man was perched on the edge of a nearby desk, doubled over with laughter, his long black hair falling elegantly over his eyes as he gasped for breath. He wore a leather jacket and one arm was slung across a ghetto blaster. It vibrated with the force of the music it emitted. Behind him, another man had entered the office. He was walking in slow motion, his face obscured by oversized comedy sunglasses. He stopped walking – one leg suspended in the air like a dog relieving itself against a tree – when McGonagall reached the ghetto blaster, switched it off and angrily demanded an explanation. The sunglasses were tossed aside, revealing a smaller pair of real spectacles and a lean, brown, familiar face.

Disaster struck.

"Morning, sir!" he called out in greeting, raising one hand to ruffle his hair. Morning, Evans! And something within Lily – her dignity perhaps – sank quietly to the bottom of her stomach. He grinned cheekily at McGonagall, unaware of the horrors to come. "Sirius and I were trying out a motivational exercise this morning."

"Consummate professionals," said the leather-clad man.

"Did you like my entrance, sir?"

"He practised it in front of the mirror."

McGonagall, who could not have known the damage she had done, folded her arms across her chest. When she spoke, her voice was low and deadly. "Pull your trousers over your underpants, Potter, this isn't the Glastonbury festival. Black, that contraption will be out of the office before the rest of the team arrives or I will sell it on the internet."

"Don't mind if you get a good price," said the man named Sirius Black, shrugging.

"Hang on," Potter interrupted. "Isn't that thievery? We're actually working to stomp that out here, sir." He pointed to his chest. "Police, see."

Lily was practically pressed against the window, a vinyl blade digging into her cheek, breath settling on the glass beneath her nose, but neither man had noticed, so she stepped back. An unwelcome shakiness had come over her, a visceral reaction that she had no hope of controlling, like a child stepping sleepily out of a nightmare. This was her disaster, that face that she hadn't seen in nearly nine years, but had committed to memory and treasured as something perfect and glowing and lost to her forever. The smile, the dimples in his cheeks, the thick black brows and hazel eyes that hid some marvellous joke; nothing had been misremembered. He had not changed, not much, though he was much taller, and had lost his awkward, collapsible-ruler lankiness to broad shoulders and sturdier arms. His glasses had changed with the fashion and his jaw had become more pronounced, but still he was perfect, still glowing, still a worthy subject of her teenage fantasies. Lily had expected him to exist as a pretty recollection, forever adolescent, but James Potter had betrayed her memory and become a man.

A man who hated her, and had earned the right to do so.

"I told you both to arrive early so that you could greet the new DS," McGonagall was saying in a voice that was distant to Lily's ears. "What I don't recall is asking you to create a makeshift disco in the office, strenuous as I'm sure your efforts have been."

"But this is for the new DS," said Black. "We're trying to make him feel welcome."

"Evans!" McGonagall called. "I doubt that she will find your antics amusing, Black, but let us get her opinion on the matter."

The last thing that Lily wanted to do was walk into the bullpen and throw herself in James Potter's face like a grenade, but it was McGonagall asking and she had no choice. But the girl she was, the girl who had known James Potter once upon a time, had mastered the art of maintaining a collected façade when in the presence of the boy who was in equal parts infuriating and intoxicating, and the adult she had become could not be prevailed upon to reveal her true feelings now, so she walked out and appeared to all assembled to be in complete control. James Potter saw her and recoiled as if she had stabbed him in the chest.

"Evans," he said immediately. True to his nature, Potter was not one to wallow in stunned silences.

"Yes," said McGonagall, frowning at the sudden change of atmosphere, the thickness that had settled in the air. "Black, Potter, allow me to introduce—"

"I know who she is," Potter interrupted. He looked from her to his friend, Black, but his eyes swiftly returned to her again. "Is this a joke?"

McGonagall bristled. "What nonsense are you talking about now, Potter? Evans is our newest DS and she will be joining this team, effective immediately, as you would have known if you had listened to my briefing a week ago, instead of burying your nose in your phone."

He wasn't paying attention to McGonagall. He was staring at Lily as if she was a ghost, which she was; Lily Evans, the awful, the heartless, the incredible vanishing girl, and while an outsider might have read a million other things into his expression, Lily could only see the remnants of a pain that she had been cruel enough to cause. "Lily?"

He made her name sound so pretty, she had forgotten that. She tilted her chin towards the light. "Hello, Potter."

"You work here now?"

"Yes."

He swallowed, and blinked hard, as if he might will her to vanish if he wished for it hard enough. "Are you serious?"

"Yes."

"Alright," he said quietly, nodding to himself. "Alright."

The apology was on her lips when suddenly, marvellously, James Potter cracked a smile that was boyish and charming and as sincere as it had ever been, saving the day, and Lily was seventeen again.

"Sir!" he said to McGonagall, looking at her but pointing at Lily, right at her heart. "How did you know what I wanted for my birthday?"

In case you missed it, this fic is complete, and I'll be updating chapters every Wednesday. I'm interested to see if anyone can guess why Lily believed James would hate her, so let me know if you've got any ideas.