And it's peaceful in the deep,
Cathedral where you cannot breathe,
No need to pray, no need to speak

'Never Let Me Go' - Florence + the Machine

The car dives underwater and everything slows down, stops, her breath trapped in her lungs because of the brutal encounter with the seat belt, blood drumming in her ears. The sudden silence is broken by the gurgle of water slipping in; her head swivels and her hand spurts out to his, stops his frenetic attempt to roll down the window.

"Castle. Stop. Stop." Her voice is too loud, foreign. It's a few seconds before he actually heeds her, and by then it's too late, water is already spilling inside, splashing and cold and too fast.

Castle's eyes stare at her like he's doubting her mental health. "Kate. We have to get out of here. Now."

Her thoughts are a jumble; she tries to order them, get past the shock of the pigeons and the bullet and Blakely's lifeless body crumbling to the ground. Her hand is still on his wrist and the warmth, the galloping beat of his pulse are too much. She lets go, gathers herself.

"No," she says. "They might be waiting for us to surface just so they can shoot us."

The writer's eyes darken; he obviously didn't think of that. The water pooling around her feet is freezing. She shivers, snags her arms around her waist. Her car is slowly sinking; the bottom must not be far now, but they haven't reached it yet.

"Still. Kate. We can't stay here."

You think so, Sherlock?

"Can you close the window?" she asks, desperate for time. She watches him try, but the water's pressure is too strong, and his efforts are in vain. He shakes his head, apologetic.

"Don't think so."

Probably won't make much of a difference. They'd run out of air quickly enough, anyway. She wonders which one is better - asphyxiation or drowning. Maybe a bullet in the head isn't so bad after all.

The front of the car hits the bottom of the water with a muffled thump, shaking them both; little by little, the Crown Vic goes back to a more horizontal position. The water is up to her knees now; she drags her legs up, tries to escape the ocean's cold, perverse kiss.

"Kate."

His voice is low, tense, thrumming with urgency. He's counting on her.

She looks at him, sees the barely contained panic in his blue eyes.

"We'll just wait until the last second before we get out. Hopefully they'll have given up by then." She tries to ignore the fact that "by then" probably means in two minutes' time, tops.

"How *are* we getting out?" he objects, face grim, teeth gritted but chattering anyway. Just like hers.

"Through the window? Pulling it down all the way?" Now that he's mentioned it, she's not even sure that it'll work.

"Think that'll work?" he echoes her thoughts, makes her wince.

Or maybe it's the water seeping through her clothes, licking at her waist.

"I don't know, Castle," she hisses. "It's not like I've tried this before."

"Oh no? You don't spend your free time running your car into the ocean and then trying to get out? I'm disappointed, Beckett."

She smiles a little, if only to reward his feeble attempt at a joke; but the dry chuckle she lets out turns into a moan when the waves rise up to her chest, sink into her bra, the sensitive skin of her breasts revolting again the icy bite of it.

Fuck. So cold. She closes her eyes and braces herself, pleads with her body. Just hold on a little longer.

"Kate."

She hears him reach out to unfasten her seat belt, grunting as he struggles with it, then letting out a slow breath as he pulls her out of her seat, closer to him. The water gets in the way, makes every move awkward, too slow; she barely feels his hands on her waist, but she can tell he's trembling too. All over. Oh God, they need to get out.

This was a stupid, stupid idea. She shouldn't have made them wait. She's not even sure she can swim now.

Oh, of course she can swim. She *has to*. Don't be stupid, Kate.

Flickering warmth at her temple; his breath, she realizes, the tantalizing glance of lips against her skin. The murmur of her name.

Enough. Enough of this. They have water up to their necks; they can't wait anymore. Kate unfolds a numb arm, reaches for the crank, gropes around before she manages to land her hand on it. Her position isn't so good; she's gonna have to go under.

"Castle?" she says, the two syllables unsteady with the force of her shaking. "Be ready to hold your breath."

She sucks in a lungful of air, and she dives in.

No.

The single syllable freezes on his lips; she's gone already.

Her dark hair pools in the water in front of him, sombre, twisting tentacles, not unlike the ones anxiety is knotting around his heart. There's barely any air left in the car; a few more seconds and the ocean will have claimed it fully.

And yet the window's not moving.

He has to smother the urge to go down and help her, because he can't, can't help; his hands are not needed. Would only get in the way. No room.

Come on, Kate. Come on.

As if on cue, he feels the glass move under his fingers. Just an inch or two down before it stills again, but that's always a start. He tries not to worry about how well he'll fit through that window; time for that later.

Right now, this extra inch means the car is completely flooded; he only has a split second to absorb all the air he can, and then water's everywhere.

Fucking freezing water, too.

The window slides down some more - halfway there - again - and again-

His heart is beating out of his chest and he wonders, terrified, how much oxygen Kate's got left, because she's been underwater longer than him, has been pushing and pulling at the crank to roll down the window.

That takes effort.

And effort takes breath.

A long time ago - in a different life, really - he might have found this exciting. Danger and the rush of adrenaline, the not knowing whether you'll get out alive; fodder for the books, of course, but also an exhilarating experience.

He might have fancied himself the hero of some James Cameron movie, trapped at the bottom of the ocean, left to choose between hypothermia and drowning; might even have found it thrilling.

But no more.

Kate is all he can think of now, her name a drowned, frantic, silent prayer in his throat, with his wild heartbeat for an organ in the background.

The window slides open all the way.

She's almost out of air when she manages to bring down the crank again, the space wide enough at last to let both of them out. Immediately she feels Castle's hands on her, or what she thinks to be his hands, a strength pulling her up, pushing her through.

Her body is frozen solid, a compact, rigid thing, and she couldn't resist even if she wanted to.

She doesn't want to. Black is tunneling into her vision and every movement is agony, which is strange, since she barely feels anything but the cold.

The cold. The cold isn't so bad anymore.

It's caressing and sweet, gentle arms enveloping her, cradling her; and all around the lovely stretch of silence. So peaceful.

She closes her eyes.

Something's wrong.

She should be swimming up to the surface, not lingering outside the car. Not waiting for him. Stupid, Beckett.

Castle clumsily wriggles his hips through the window, relief spreading when he does make it out, the buoyancy of the water helping. His foot catches on the door and he struggles to set it free, body too heavy, too slow. Taking too much time.

Air. He needs air.

He yanks his ankle loose, a dizzy sense of triumph buzzing in his ears, quickly crushed when he turns to Kate's unmoving form.

Despair swirls through him, grants him one more precious moment of clarity. All he needs.

He grabs her, hooking an arm around her neck and letting his fingers curl under her opposite armpit, and he pushes himself off the bottom, scraping together all the strength he can find in his quitting body.

Daylight shimmers above him, so appealing. So far away.

Kate.