Author's Notes: Thank you so, so much to the incredibly helpful and talented 404, who was kind enough to give me a very thorough beta and a great number of suggestions, many of which I took.

I may dabble in this verse in the future, but I'm pretty happy with this as an end point for this fic. I hope you enjoyed the trip!

Conditioned Response – Chapter 5

It's three weeks later when a voice rises up from the narrow bed beside his, apropos of nothing, just after Steve thinks Bucky's finally drifted off to sleep.

"That's the order they used to give me. When they were trying to make my training stick."

The room's dark. Some of the city light filters in between the curtains in long, pale strips, but it's not enough to make out an expression, or even a face. Bucky's just a silhouette, a mound beneath some blankets in the dark.

That's the order they used to give me. Steve rewinds the events of the evening, then the afternoon that came before, trying to place the reference.

It's been a good day.

Bucky took Clint on at ping-pong and whipped him soundly, gloated about it with relentless cheer and a smug smile. They walked through Central Park to see the statue of Alice, a child's dream in bronze – sculpted after their time, but a landmark now, apparently. At dinner, Bucky had two bowls of Bruce's potato chowder, three rolls, and a glass of milk. When he wanted more, he took more; he didn't just lower his head and go still the way he used to, unwilling to touch anything without permission.

It's been more than a good day. It's been a great day – so Steve casts his mind further back, looking for answers elsewhere, instead.

"What I said," he asks at last, carefully, "at the hotel?"

"Don't move," Bucky confirms, and his voice is tight.

Steve wishes he could see. He wants to know what those words have done to his best friend's face, but he's sure that's why Bucky waited until now – for the night to cover him up and keep him hidden.

"It started out pretty easy, you know? There was – it was just this empty room. They'd give the order and they'd leave. So I'd stand there." He pauses for an instant; Steve can picture him licking at his lips, the way he does sometimes when he's nervous. "It was a long time sometimes, but not so bad. Nothing I couldn't handle."

The shadow that's Bucky shifts a little, a movement Steve can't quite read. The knob to turn on the lamp is twelve inches away on the bedside table, but that might as well be miles.

"So they made it harder." Bucky's tone is flat and remote, like he's reading off a shopping list. "They'd do things to the floor. Heat it, freeze it. Once they broke glass." Steve can hear him swallow. "And they'd want me to stand there."

All of a sudden, dinner's a dead weight in Steve's stomach, and the dark blooms with images he can't blink away: Bucky, muscles strung taut and strained, holding some pose for hours or days. Bucky stock-still in a puddle of his own blood, feet flush on broken glass. Bucky's face, schooled expressionless, blank despite the pain. Blank because it has to be.

When the words come again they lurch a little, like they're being dragged out into the open. "I got good at it. Not moving." Steve can hear the bitter grimace. "But however good I got –" Bucky breaks off. When he starts up again, there's a waver in his voice that wasn't there before. "I couldn't do it right."

Buck's always been good at pretending things are okay.

He'd lost his job once, when the factory shut down – kept them both going on a wing and a prayer – and it'd been six weeks until Steve had even known something was wrong. But between one breath and the next, whatever bravado's brought Bucky this far deserts him.

Steve reaches out across the space between them and offers his hand. In the unlit room, it's an invisible gesture, so he lets the weight of it settle on Buck's blankets, lets him know it's there. After a few seconds, he feels warm fingers thread into his own.

"They'd have me hold things," Bucky continues, and Steve can hear desperation creeping in around the edges. "With my real hand. Sometimes just weight, and I had to keep my arm up." There are tremors in the fingers that clasp Steve's. "Or sometimes this – I don't know. This thing. It got real hot, like a poker in a fire."

Steve closes his eyes, as if to keep from seeing, but he sees it anyway. And as he sweeps his thumb in slow arcs across Bucky's palm, an old soothing gesture, the patches gone scarred and calloused read like braille. Steve can't keep from imagining the wounds burned in, session after session, until the skin grows rough enough to protect itself. Until Bucky stands there and accepts it.

Here and now, in the adjacent bed, Bucky makes a terrible, breathless sound that might be a laugh. "And once – Christ, Stevie, they didn't feed me. I would've given my other arm for something like dinner tonight, and they – gave the order. And they put this piece of bread in my mouth."

Steve can picture that, too, however much he doesn't want to. It's so real, it feels like it's flaying him open: Bucky's eyes dull and empty, aiming for stoicism – Bucky opening his mouth on command, even though he knows what's coming. He thinks of white coats jotting notes while Buck fights not to swallow, and it's the worst thought he's ever had.

The cold rush of horror bottoms him out. He can feel it all the way down in his toes, a sick wave that leaves him light-headed.

"It was like I couldn't win. Every time I'd say, 'Whatever they throw at me, I can take it.' And every time they'd prove me wrong." The words grind to a stop. Steve can hear him breathing, ragged but soft, trying to be calm.

"Buck," Steve begins. It's over, he wants to say. But the man beside him starts talking again, as though he's afraid the interruption will derail him.

"So I'd fuck up," he says. "I always did, in the end. And then we'd have to go –" Bucky trails off, and the beat of silence that follows is suffocating. Something worse is coming, Steve knows, but he can't fathom worse.

"Buck –"

"To a different – another room. They –" The sentence splinters when Bucky's voice finally breaks. Steve can hear him breathing; the breaths are loud and close together like he's drowning, gulping air.

Steve squeezes Bucky's hand, tries to bring him back. He's reaching for the lamp when Bucky grates out, at last:

"The conditioning chamber," The syllables are raw, like he's pulled the admission out by force. Below the blankets, Bucky's form shudders visibly, and the hand holding Steve's has gone cold.

For a few seconds the only sound is Bucky breathing, trying to control himself – and, somewhere in the city below them, a car alarm bleating.

"And I always thought – next time I'd try harder. I'd – I'd do whatever they wanted." There's that sound again, too awful to be laughter, only now it's rough at the edges, like old cloth coming unraveled. "They coulda had me do anything."

It's not hard to hear the self-loathing. Bucky's voice is thick with it, with disgust and shame and a hundred other things too subtle to put names to.

And Steve – Steve's never felt anything like the bone-deep rage that settles over him now. It comes all at once, a driving need to track down every last monster who stood by and let this happen.

He's fought a war, killed men, but never before has he felt an impulse like this one, hot and immediate, to end a life – personally, deliberately, with his own bare hands.

But the men who did this are dead already, most of them – dead after long, full lives, while the damage they inflicted still eats Bucky up inside. All of a sudden, the anger is gone, leaving something sick and weary in its place.

There's things he wishes he could do, or say, or fix. But it seems like he's half a century too late for all of them.

All he's got is now.

So Steve says, "Hey," and he's not surprised to find that his throat is tight. "You want company over there?"

There's a pause, and Bucky disentangles their hands. The mattress creaks when he scoots over, and that's answer enough.

Steve sits on the edge of the blankets, and he sets his hand on Bucky's shoulder – the flesh one, the one without the memories attached. He can feel the muscles standing out, rigid as steel; he can feel Bucky shaking.

He remembers winters in Brooklyn, when the cold would get in his lungs so that every gasp was a struggle. He remembers Bucky sitting like this, so close Steve could feel his warmth through the covers. He remembers waking from fever dreams, coughing so hard he retched, and Bucky there with a bucket and a cup of water.

Steve misses those days, suddenly and fiercely. He misses the simplicity of them. He misses knowing that whatever happened – whatever else went wrong – Bucky was safe, and whole, and strong.

"Buck," he says, after a while. "You know that's all done with. Right?"

There's no reply for a long moment. "I almost killed you," Bucky says at last. He holds it up like a shield – like he's daring Steve to say otherwise.

But Steve knows better.

He thinks of the long, sleek lines of the Insight carrier. He thinks of three separate shots that missed vital organs. He thinks of Bucky, back before whatever hellish training Hydra put him through, back before even his sniper work in the Army – a gap-toothed twelve-year-old with an infectious grin and skinned knees, in the abandoned lot where Mikey's Lumber used to be. He remembers Buck lining up cans on the low brick wall and knocking them down with a sling at fifty paces, neat as you please.

Then he thinks of Bucky's voice, choked with remembered pain, saying, "They coulda had me do anything."

But when it came down to it, they couldn't.

Steve says none of that. "I don't die that easy," he tells Bucky, instead. "Too stubborn to leave you on your own again, I guess."

He feels the inhale when Bucky's chest hitches, a little stutter and then a sharp gust out. Another comes on its heels, in perfect silence.

"You better mean that, punk." Bucky's voice is rough, strangled. "I'm gonna hold you to it."

Steve's aware of everything in that moment: the warmth of Bucky's side through the blanket; the stinging at the corners of his own eyes; the city lights outside the window, filtering in through the curtains.

"Hey," he tells his best friend. "That's fine by me."