A/N: So, I saw something a little while back about how the Winter Soldier's mask locked him down and trapped him in, and that just really stuck with me. I finally was able to put together a story that explored that a little more, and while I was looking for a setting, I watched Civil War again and felt like I needed some nice h/c after the fight with Tony, and it all just fit together so well. Voila.

(Also, I figured Steve had to be pissed at how close Tony came to actually killing Bucky. I am. So we'll start with that.)

One day, Steve promised himself, one day he was going to set the record straight, clear their names, and make it up with the rest of the Avengers. Even Tony. Especially Tony. Making up with Tony was in the foreseeable future. But forgiveness? Steve didn't think he'd ever be able to grant him that. Not for everything.

At first, when Tony had attacked Bucky, the only thought on Steve's mind had been to stop him. Tony was angry, Bucky could take a few hits, and Steve could talk him down. It became very clear very quickly that that wasn't going to happen, and the fight soon became just him and Bucky against another threat. They fought together, in sync as if they'd never been out of it, as if it had been merely days since the last time they'd done it instead of seventy-one years. Just him and Bucky, like it always was. But then Steve went down. Just for a minute, but he was down, and Bucky protected him like he always did. And Tony crossed the line.

The horror in Bucky's eyes as he stared at where his arm should have been was going to haunt Steve for a long time. The barely audible grunt as Tony shot him in the back wouldn't stop echoing in his ears.

Steve didn't remember a lot of the fight after that.

He remembered a rage he hadn't felt since the train. He remembered something in the back of his head telling him to pull his punches, not to do anything he would regret. And he remembered ignoring it when Tony's boot came down on Bucky's face and something cracked in Steve's soul along with Bucky's bones.

When it was over, Steve picked Bucky up off the floor. His eyes were blank and far away, like the time he'd picked him up off the table in Italy. He'd dropped the shield without a second thought. He'd picked it up for Bucky. Putting it down for him was easy. The sound pulled Bucky back into the moment, and Steve felt him looking at him as it clanged to the floor. He tightened his grip on Bucky's arm, assuring him it was alright.

Even with the elevator, the climb to the top was long and painful. Bucky had stopped responding to him before they were a third of the way up, using all his energy to focus on keeping upright. By the time they hit the top, his eyes were far away again, his breathing was ragged, and Steve suspected that decades of Hydra conditioning were all that was keeping him on his feet. His heart sank when T'Challa appeared from behind a snow-covered rock—he had nothing left to fight with.

Looking back, he was pretty sure the king explained twice what had happened before it hit Steve that he wasn't going to attack him. It took another long moment for his offer of help to sink in, and he didn't fully grasp it until Bucky's weight suddenly lightened against him as T'Challa moved in to support him from the other side.

Now they were on the plane, headed for Wakanda. Bucky had passed out before they got on board. Hell, after the beating he'd taken, Steve was surprised he'd made it to the top, super soldier or not. He recognized the symptoms of shock, something he hadn't seen up close since the war, and did his best to make Bucky comfortable with the limited medical supplies on board. Thankfully, those limited supplies included an oxygen tank and mask. There was no doubt in Steve's mind that the bolt of energy to the back would have killed him outright if not for his advanced healing abilities. It had done enough damage as it was—the longer they had walked, the more Bucky's breath had rattled in a way that made Steve nervous.

Once Bucky was taken care of, breathing better and strapped into the narrow cot to keep him secure in case of rough air, T'Challa had taken off, assuring him that the medics in Wakanda would take good care of his friend. Steve cleaned the alarming amount of blood from Bucky's face—more for his own peace of mind than anything else. He knew they were both going to need medical treatment, but he also knew Bucky healed almost as fast as he did, and that Bucky would be conscious and would probably be able to walk off the plane under his own steam by the time they got to Wakanda—he just couldn't keep looking at the blood and thinking about how close he'd come to losing him again.

Things got a little fuzzy after that—the pounding in Steve's head ratcheted up until everything faded into white noise. He didn't realize he'd passed out until he was waking up.

Everything still hurt, but his head was clearer, and he craned his neck to see what it was that had woken him. Still strapped in to the cot across from his seat, Bucky was stirring, not quite awake, making small sounds of distress. As he crossed to his friend, Bucky's eyes snapped open and his uneasy writhing ramped up into panicked flailing. He was saying something Steve couldn't catch through the oxygen mask, eyes wide with fear. Steve dropped to his side and began undoing the straps holding him in—he was fighting them so hard they were drawing blood.

"Hey, it's okay, I'll get you out," Steve assured him. "Bucky, easy, it's me," he added when his friend didn't seem to hear him. He got the straps undone as fast as he could, which wasn't easy with as much as Bucky was straining against them. The last strap clicked open, Steve staggered backwards as Bucky kicked him in the chest, and Bucky pulled himself up against the wall behind him, making himself as small as possible. He was clawing at the oxygen mask with his good hand, sharp clicks and sparks flying from what was left of his metal arm as it moved erratically.

"Bucky," Steve said, moving back to the cot. Bucky was still fighting the oxygen mask, ignoring Steve in his struggle to get it off. "Buck, it's me." He placed his hands tentatively on Bucky's shoulders, and the wounded soldier snapped wide, frightened eyes up to look at him. "It's Steve," he said. "I'm right here, it's okay. You're okay."

"Steve?" It came out a little muffled through the mask, but Steve caught it just fine, and the beginnings of clarity settled into Bucky's eyes.

"Yeah. Yeah, I'm here," he assured him. From the front of the plane, he felt T'Challa's eyes on them, and he turned to nod and assure the king that he had this under control. T'Challa watched them a moment longer before nodding and turning his eyes back to the sky.

"Steve," Bucky repeated, drawing his attention back. "Get it off me, Steve, get it off! Get it off, get it off! Steve, get it—" His thrashing arm finally managed to pull the mask from his face.

"Whoa, Bucky, no, you gotta leave that on, man," Steve said, reaching for the mask. Bucky was panting heavily, but his breathing was still labored, as though each of the deep breaths hurt.

"No!" Bucky snapped, slapping Steve's hand away. "No!" His eyes widened suddenly and his tone changed and he pulled back as far as he could, pressing himself into the wall and shielding himself with his arm. "I'm sorry! I'll be good, I'll be good, I promise," he said, his voice small and childlike. "Don't put it back, please, I'm sorry."

Steve gaped, his hands falling from Bucky's shoulders.

"I'm sorry," Bucky whispered again.

"Bucky," Steve said gently, swallowing down the rage churning in his stomach. He didn't know what was going on yet, but he knew it had to do with Hydra, and he really, really wanted to punch something.

"Bucky," he said again. "It's okay. I'm not gonna hurt you. You know that, right?" Bucky didn't respond, and Steve reached out carefully for his shoulder. "Tell me you know who I am," he said, making sure to phrase it like a question, not an order. He wasn't sure where Bucky's head was right now.

For a moment, nothing, but then Bucky raised his head up a little bit, looking out from behind his arm. His eyes met Steve's, and, after a moment, calm started to settle back in. "Steve," he said softly. "You're Steve. You found me, and you…" He swallowed hard, but his voice was steadier when it came back. "I know you won't hurt me." He sounded like he believed it.

"That's right," Steve replied, smiling sadly. He wondered how many times since 1945 Bucky had woken up screaming. "I'm sorry I scared you."

"No," Bucky said, shaking his head. "I'm sorry. I shouldn't've, I mean, I didn't know—"

"It's okay," Steve cut him off. In retrospect, strapping him down had probably been a bad idea.

Bucky studied him for a long moment, trying to figure out if he meant it, before finally giving him a tiny, grateful smile and nodding. He relaxed, and Steve moved to help him sit more comfortably on the cot, wincing along with every pained hiss that escaped Bucky' lips. He looked terrible. A spectacular bruise covered most of the left half of his face, covering what was at the very least a cracked cheekbone. The darkening purple made his already pale skin look even paler, washed out and sick. There was dried blood Steve had missed earlier around his nose and matting his hair and eyebrows, and his eyes were bloodshot and still a little wild. The occasional spark still shot out of the severed wires in his shoulder. Everything else was still covered by his combat gear, and Steve had no doubt it looked just as bad.

"You okay?" he asked. It was kind of a stupid question, but it was all relative at this point, and he was glad when Bucky nodded.

"What about you?" Bucky asked, concern creeping into his eyes as he looked Steve over.

"I'm good," Steve replied. Bucky narrowed his eyes suspiciously. "Alright," Steve amended. He figured he looked almost as bad as Bucky did. "So maybe not good, but I'll make it." Bucky glared at him a moment longer, then inclined his head as if agreeing that was as good as he could ask for right now.

"You want some water?" Steve asked. Bucky nodded again, and Steve passed him a canteen. There was a brief awkward moment as Steve realized Bucky couldn't open it, but he breezed past it and unscrewed the lid as if he'd been intending to do so all along. Bucky scowled briefly at his missing arm, but nodded in thanks and took the container from Steve.

"Does it hurt?" Steve couldn't help asking, nodding at the missing limb. He'd often wondered if he felt anything with the metal.

"Like hell," Bucky replied without heat, taking a drink of the water. "I could never feel much with it…just pressure and motion, that sort of thing," he seemed to feel the need to elaborate. "But they had to connect the thing to my nerves so I could use it, and it always hurt when part of it got broken." He took another drink. "This definitely counts as being broken."

"I'm sorry," Steve said.

"I'll live," Bucky told him, a ghost of his old smile in his voice.

He winced as he set down the canteen and shifted on the cot.

"About the mask," Steve started. Bucky's breathing was better now that he wasn't panicking, but he still didn't sound good.

"I can't put it on, Steve, I can't," Bucky said quickly—his breathing resuming its terrified gallop just as quickly. Steve wondered briefly if he was imagining that he could hear his heartbeat racing.

"I'm not gonna make you," Steve replied just as swiftly, hoping to stave off another panic attack. He held up his hands in a gesture of surrender, and Bucky started to calm down again. "But can you tell me why?" Bucky turned his head away. "You're just…You're not breathing so good, man, and I just want to make sure you're alright," Steve explained.

Bucky kept staring at the wall, and Steve sighed. He obviously didn't want to talk about whatever Hydra had done to him, and while Steve wanted to know what had happened to Bucky while he hadn't been there to save him, he didn't want to push him into something he wasn't ready for. And as long as he stayed calm, well, he was breathing a little better. "You know what, never mind," he told him. "It's okay. You've got a reason, and that's good enough for me."

Bucky turned back to him. "Really?" he asked in a small voice.

Steve nodded. "You don't have to tell me anything you don't want to."

Bucky stared at him, surprised, and Steve's heart broke a little. Of course he wasn't used to people giving him options. "Thanks," he whispered.

Steve nodded and unfolded his legs from where he was crouching to sit against Bucky's cot. He would have liked to sit up there next to him, but his left leg was protesting its existence loudly, and he didn't think it would push him up the foot and a half it would take to get there.

They sat in silence for a little while. The gentle vibrations of the plane had nearly lulled Steve back to sleep when Bucky's voice pulled him back to the present.

"They used to put a mask on me," Bucky said softly. Steve turned to look at his friend, but Bucky was staring intently at his hand. No need to ask who 'they' were. "There was one to help me breathe in the cryo-tank, and another one they would…" He sighed. "I was almost always wearing one or the other. It was like…" He sighed again and ran his hand through his hair, obviously having trouble finding the words he wanted.

"You remember D.C.?" he asked quietly. Steve nodded. He didn't think he'd ever forget. "The mask I was wearing, it wasn't, it wasn't to make me look intimidating, or, or to keep you from recognizing me, or...After Zola died, no one in Hydra knew who I used to be. I was just 'the Asset'. No one knew you would recognize me, although Pierce put the pieces together pretty quickly after you did."

He sighed deeply, and his voice was shaking a little when it came back. "The mask was for me." His voice was barely a whisper now. "I used to fight them. Even after I'd forgotten who I was, I would fight, and they would hurt me and they would strap me down so I couldn't, then I…" He huffed a soft, humorless laugh. "When I couldn't hit them I would try to bite them, and they would put the mask on me, and I couldn't move, and I couldn't fight back, and I couldn't bite or even scream because it all just caught inside the mask, and I couldn't…I couldn't do anything." He swallowed hard, and Steve could just see his eyes glistening behind his hair.

"The mask was to remind me of my place," he said, so softly Steve had to strain to hear. "Even after I…after I broke, and I quit fighting, and I did whatever they told me. Even after they won. They made me wear it almost…almost all the time. It was like putting a muzzle on a dog. The mask was there to remind me who…" He swallowed again, his voice seconds away from breaking down completely. "To remind me who I belonged to."

Steve swallowed down the urge to be sick. "Bucky…"

"And I know it's stupid, but when I woke up and felt that on my face, I was being locked back in again, and I just, I can't do it, Steve, I'm sorry, I can—I can't!" he finished, his voice fracturing as he did and shattering Steve's heart along with it.

"It's not stupid, Buck," Steve said softly.

Bucky shook his head and sniffed and folded down in on himself, shaking silently as he cried. Ignoring the protests of his leg, Steve shoved himself up and onto the cot, scooping Bucky into his arms and holding him tightly. "It's okay, Bucky," he whispered. "It's gonna be okay."

Bucky tensed at first when Steve grabbed him, but at Steve's words, he relaxed and let go completely, sobbing into his friend's chest. Steve gripped him tighter and just held on.

He wasn't sure how long they sat there, and he was grateful that T'Challa was very tactfully and studiously ignoring them. Bucky would be embarrassed enough as it was when this was over—he had always preferred to keep his emotions to himself. Steve was one of the very few people Bucky had ever allowed to see him cry, and the last time Steve had seen it was the night after Azzano, in 1943.

Bucky had stopped sobbing a little while ago, but he was still trembling, the occasional sniffle coming from somewhere behind his hair. He stilled at last, abruptly pushing away from Steve and sitting up, scrubbing at his face with his good hand. "Sorry," he said roughly, not looking up.

"It's okay, Buck," Steve told him. Bucky said nothing, and Steve could see his skin reddening between the strands of hair hiding his face. He sighed. It was one thing for Bucky to be embarrassed for breaking down in front of a stranger, but Steve never wanted him to feel like he had to hide himself from him. Old Bucky knew Steve would never judge him for having or showing emotion, and he hoped this Bucky knew it too and just needed reminding. A small smile tugged at the corner of his mouth as a ninety-two-year-old conversation popped into his head. "You don't need to be embarrassed about it or anything. It's okay to let someone help you when you need it. And I'm not gonna make fun of you or nothin'. I promise," Steve assured him, quoting a seven-year-old Bucky.

That got Bucky to look at him, although his eyebrows were knitted together in confusion and just a little bit of concern. Just as Steve started to realize how stupid it was to reference something Bucky obviously wouldn't remember, he saw the spark of recollection catch in Bucky's eyes. Bucky turned away, shaking his head.

"You're a punk, you know that?" Bucky said quietly, a small smile growing in spite of himself.

"Hey, I'm just repeating the words of the wise, jerk," Steve replied good-naturedly, bumping Bucky's arm carefully with his elbow. "But you know I mean it, right?"

"Yeah," Bucky said softly. "I know. And I don't want to seem like, I mean, I don't want you to think I don't…" He let out a frustrated sigh, pinching the bridge of his nose. "I used to be more articulate than this, didn't I?"

"Only with girls," Steve teased, hoping his tone would tell Bucky it wasn't anything to worry about. He had noticed that stress seemed to impair Bucky's ability to express himself—given the past seventy-one years, it made sense that he wasn't exactly used to talking to people anymore, and Steve was prepared to be patient until he was. He smirked, and he wasn't fast enough to dodge the smack Bucky directed at his leg. "Ow!" The corner of Bucky's mouth twitched up.

"I just, I hope you know," Bucky said slowly, his face turning serious again. "It may not always seem like it, but I…You're here, when you could be…" He took a deep breath, taking the time to select his words. "I know things are screwed up right now, and a lot of it's my fault. But you're still here. With me. And I can't tell you how much that means to me." He twitched his eyes up to meet Steve's, waiting for his reaction.

Steve swallowed down a tightness in his throat. "End of the line, pal," he said softly, ignoring the prickling in his eyes and smiling at his friend.

Bucky returned the smile, and this time, it reached his eyes. "End of the line," he repeated.