He is flipping the knife when his arm fails.
It is night. The knife is in his hands because the motion keeps him from sleeping. He has tried not to sleep since the time he dreamed, but his body is refusing to cooperate on that front. It keeps slipping back into unconsciousness before he can catch it. This happened mid-step on the way back to DC. He'd woken up maybe minutes or maybe hours later, face scraped from the collision with the ground. The Soldier has the sense that sleep is at least as vital to his body as water, but water doesn't cause dreams.
In one instant his hand is whirring, tilting at the wrist, and in the next the entire limb goes slack. The other hand catches the knife on instinct, but by the blade rather than the handle because he couldn't properly execute the toss. It opens a gash along his palm, blood leaking out of the wound. The pain, while not the worst he's felt in recent memory, is sharp and unexpected and fully wakes him up.
He files the sensation away as a potential future motivator and sits up straight, examining the opposite arm.
The Soldier is in an alley, because while his body has ceased to hurt so badly, it is still weak. Intimidating the homeless squatters out of an alley relatively near the Smithsonian with his knife is easier than locating and casing an empty building. Also, he thinks he likes the unobstructed view of the sky.
Under the sleeves of the jacket and shirt, his arm is still cool to the touch. It has not overheated. That is the second thing he notes upon touching it with the opposite hand. The first thing he notices is that his left arm perceives neither the touch nor the fabric.
The left arm feels nothing at all.
Staring, head tilting slightly to the side, the Soldier taps the arm, then takes the wrist and shakes it a little, as though that can jostle it back into functioning.
Up to this moment, he had been able to classify the day as a success. Yes, it had been full of aching, exhaustion, and clothing that attempted to slide off his body in a way in hadn't earlier in the week, but he had smiled for possibly the first time in his life as a Soldier.
It had happened in the Smithsonian. He had returned there that morning and observed until the exhibit was closing. The Captain America mannequin was still missing from the display, and the Soldier's mind drifted to the uniform he put several bullets through. It couldn't be the same one, could it? Even if it was, he wasn't sure he felt guilty. Steve was with him until the end of the line. Captain America
[Капитан Америка мёртв и враг]
was a title, a symbol. He'd never needed a symbol, only a directive.
He'd spend hours watching the footage of Barnes. Motionless, eyes locked on screen. He was no longer so interested in the locations of the segments, the where and the why and straining for memories. But the five seconds of footage of Barnes laughing, that had him rapt. There was no audio accompaniment, and he couldn't read lips—not in English—well enough to tell what was said. He couldn't remember. But eventually he stopped struggling to, allowed himself to let the moment wash over him again and again.
And then he smiled.
It wasn't a memory. He wasn't imitating the footage, hadn't planned to respond at all. But Steve was grinning and Barnes was laughing and suddenly, there was a small, hesitant smile on the Soldier's face. He found that everything ached slightly less when he was smiling.
He is not smiling now, struggling to pull the jacket and shirt away from a shoulder that is completely unresponsive.
There is no damage to the external plating of the limb. There isn't even a scratch in the paint that forms the star. The plates can retract and his mind wills the motion, but his arm does not respond. The Soldier's other hand, still dripping red, reaches over. His fingernails slide below one of the plates easily. He thinks his nails have grown the way the hair on his face has. When he gently lifts the plate up, he angles his hand so as not to leak blood into the interior circuitry. Nothing looks broken. He lowers the plate, repeats the process with another. And another. Some he cannot check, because the arm will not hold itself up and he can't force it into a visible angle and lift the plating at the same time, but in what he can see, there is no damaged part or foreign body. It has simply shut down.
Does HYDRA have a kill switch? Why activate it a week after he disappeared? Perhaps they have tracked him and they want to take him back in, but he sees no reason why they wouldn't tranquilize him from a distance if that is their goal. He can't use the left arm while he is unconscious, and he can still fight without it.
He likely will not fight well in his current state, but he can put up a struggle.
Retrieving the knife, he listens for any ambush or approach, evaluating what moves he can execute with the left arm disabled and what compensations he will have to make in both attack and defense. He pulls the shirt and jacket back over himself. Neither will stop blades or bullets, but there is at least some protection offered by the layers. The Soldier waits.
His body attempts to lapse back into unconsciousness, and he drives the point of the blade into his leg. Not deeply. Not near anything vital. The Soldier knows how to inflict pain without causing debilitating injury. He jolts, awake again.
This process repeats twice more over an hour or so before the Soldier remembers that infections exist and the knife is not exactly sterile. He is not sure that his body can currently overcome gangrene and he would prefer not to lose a leg, so he slips the knife back into its sheath and waits with the functioning hand on the handle.
When he sleeps he dreams of ice. He tries to pull himself out of the ice and metal breaks away each time his hand moves.
He wakes up shivering. His left arm is no longer cool, matching the temperature of the air around him. Out of everything wrong with his body at the moment, this is the most troublesome. Currently, every part of the arm that he can observe is salvageable. If it overheats, that may no longer be the case.
The Soldier considers his options and decides that, even if his limbs are going to begin failing one by one, he would prefer not to wait around for that to happen. The smiling from the day prior, he would prefer that. A long stretch of time passes before he is able to maneuver the nonfunctioning hand into the pocket of the jacket to adequately conceal it—he has never realized how heavy the arm is when it is immobile, because it has never been immobile—but time doesn't much matter when there are no deadlines for success or mission reports to be delivered.
He is nearly inside the Smithsonian when he hears the voice.
"You look like hell, Bucky."
He doesn't know the voice. But the name stops him and he turns. With Steve, recognition was instantaneous. Here, it takes a moment to realize this is the man with the wings. He doesn't have the wings now.
The Soldier still doesn't understand what "hell" means, or if "hell" is different from "the hell."
"You were in Brooklyn," he says, because he thinks the man with the wings is the one Steve said he met on the helicarrier. No one else comes to mind.
"Yeah, we were." He tilted his head toward the security cameras. "Until we picked you up on those."
The Soldier realizes that the concentrated effort he made during his first visit to conceal his face from every camera had been forgotten the second time around. He can see what little life he likely has left stretched out before him, and it consists of running back and forth away from capture and detection. He thinks that is a game, but he doesn't recall the name and has no interest in playing.
"Walk with me, would you?" the man who had the wings asks. "Just to talk."
This one, he thinks, would not approach him without backup. This one is armed. This is potentially an ambush. He can run. He can disable the threat and disappear. But he is also tired. If he runs, they will pursue him again. Perhaps he can convince this one to stop. He cannot convince Steve, but if Steve's aid falls through, maybe he will eventually terminate the pursuit.
And the Soldier is in need of repair. It seems he has some programmed directive to seek out maintenance, because he is moving toward the man who had the wings before consciously deciding to do so. "I don't know how far I can walk." It is an idiotic thing to admit, but better to clue a potential threat into a weakness and have them potentially overestimate it than to ignore it and collapse in front of said threat.
"All right." If that information changed the man's strategy at all, it does not show on his features. "Then how do you feel about pizza?"
A/N: My personal headcanon is that Bucky's arm runs off of his caloric intake, which probably makes no sense scientifically, but hey, according to the Winter Soldier art book detailing the movie production, his arm is supposed to be more advanced than Stark Industries technology, so let's just assume it can be done in universe. It struck me as the most efficient way to maintain its power and the least troublesome for HYDRA to deal with (It's probably easier to throw a Snickers at the Soldier during a mission or shoot glucose into him than it is to open the arm and swap out batteries or charge him or anything).
And now I'm imagining a "have a Snickers" commercial with Bucky Barnes and I just need to stop.
Point being, my theory is that once the Soldier's body slips to a certain point in starvation mode, there's not enough readily available to power the arm without cannibalizing the body's own muscle and fat tissue, which would happen at too slow of a rate to provide the constant fuel needed to function, so the arm just stops. I also imagine it takes a hell of a lot to power that arm, so it would likely shut down a while before the rest of him.
Translations for the Russian are as follows:
Капитан Америка мёртв и враг = Captain America is dead and the enemy