Then it went quiet; no more shots.

"A bunch of them went down in to a bunker by the look of the heat signals." Stark said.

"Don't pursue." Rogers said. Bucky was a stone's throw away, turning his head this way and that, he'd seen Barton now, and Stark, and, by the way he was looking at the space behind and to the left of Rogers, he knew Romanoff was there. Now he looked scared. "Bucky, it's OK." No response. He was in there, he had to be. "Bucky, come on, we're not going to hurt you. They will, we won't." Bucky froze stock still, staring at Rogers. Rogers held out a hand to him. Bucky stayed frozen, panting for breath. For a long moment, neither of them moved. Then, without warning, Bucky launched himself at Rogers. Rogers brought his hands up instinctively and caught the metal arm just short of his throat. The second arm punched him hard in the stomach, knocking the breath out of him.

"Cap?" Barton asked. Rogers dropped and rolled away. Bucky drew a pistol. Rogers dashed for his shield. A shot flew over his head. He grabbed the shield in time to block the second. He dropped to a crouch, hiding as much of himself as he could from Bucky's fire. If Bucky turned on Barton or Romanoff, he'd kill them. He'd come damn close to killing Romanoff before.

"Do it." Bucky rushed him. Rogers took the impact of the metal arm through his shield, but he still felt it jar his shoulder. Bucky was trying to push him down, he was winning. Then Bucky yelped and jumped away. Rogers lowered his shield. A black arrow shaft was sticking out of his leg, half way between knee and hip, adding to the blood that Bucky was covered in.

"It's in." Barton said.

"Now you just contain him for five minutes." O'Malley put in.

"Easier said than done by the look of it." Stark said, landing behind Bucky. "OK, let's see how strong you are." Bucky turned, breaking the shaft off, and leapt at Stark. "Oh, that strong." Stark cut Bucky's legs out from under him. Bucky dropped but rolled straight back to his feet. He lunged at Stark, real arm leading, then changed at the last moment and grabbed Stark's neck with the metal one. Stark grabbed the metal arm and tried to prise it off. "When this is over, I need to look at these gears." Rogers grabbed Bucky round the waist and pulled him away. Bucky pulled himself up and over Rogers's head, backwards. Rogers turned, but didn't react in time to keep the metal fist away from his head. He doubled over, white light flashing across his eyes.

"Just watch the metal bit, and we'll be fine." Stark was keeping Bucky busy. Something banged somewhere as Rogers hit Bucky in the ribs, hard enough to knock him over. He was difficult to hurt. He couldn't worry about that right now.

"Help." That was Barton. "Genuinely, I need help here. They're coming up to the roof, armoured and fast." Bucky regained his feet and rushed them again.

"Stark, go." Rogers ordered. Stark took off. Bucky jumped for Stark's leg and missed. He turned to Rogers. He didn't look scared any more. He looked… nothing. He looked emotionless, like he had the first time they'd met this century, when he'd been after Fury. They collided. It took almost everything Rogers could give just to hold the metal arm. He saw Bucky's leg come up to kick, sidestepped and let Bucky fall past him, then back-kicked him hard. He didn't even seem to feel it. He turned round with another pistol drawn – how many of them did he carry? Rogers ran at him, shield between the gun and his torso, head ducked. Bucky dropped the gun and jumped up at him, knife in hand, but he seemed to misjudge the jump. He fell short. The knife scraped down the vibranium. The knife came up again, this time aiming for his gut. Rogers pushed down with the shield, Bucky stumbled, but recovered quickly. "Bucky, don't do this. You don't have to-"

"Shut up." Bucky launched himself at Rogers again. It looked as if Barton's arrow hadn't injected. He wasn't going down, he wasn't even slow. Maybe he'd do better dodging than trying to catch every blow. He wasn't used to fighting somebody this quick and with this much behind the blows. Then Romanoff was there. She wasn't strong, but she was quicker than Bucky was. Between them, they could hold him. Bucky stood on a corpse and slipped, dropping to one knee. He rolled straight out of it and back up, he was running with blood on that leg. Romanoff met him first. As soon as he got any ground with her, Rogers intervened, then she did the same for him. It felt like minutes of that before Stark landed again.

"We got containment on the roof. Did that stuff even go in?"

"Just give it time. Can you hold him for another five?" O'Malley asked.

It was taking Bucky longer to get up now. He'd bounced up when they'd started, now he took the impact, took a breath, then got back up. And it kept on, every time they knocked Bucky down, it took him a little longer to get up again, he was shaking his head as though trying to clear it, he must have felt awful.

"I'm sorry, Buck." Rogers breathed as he blocked a punch from the metal arm and jabbed Bucky in the guts with his right hand. Bucky didn't fall from that blow, he fell because Romanoff had kicked him in the back of the knee again. His leg jerked and crumpled. Bucky caught himself on hands and knees, breathing hard. He stayed there, frozen, tense, he looked terrified. They had to do this.

Bucky got his feet under himself and launched himself at Romanoff.

It was maybe a minute and a half before Stark pulled Bucky over backwards. Bucky twisted in mid air and caught himself, but he didn't get up. He just knelt there, gasping and shaking his head, swaying slightly. He was shifting his weight as though he wanted to try to get up, but he never got further than hands and knees. "Doc, he's off his feet." Rogers reported.

As he did, Bucky fell on to his side. He thrashed himself back on to his front, just about got to hands and knees, made a clumsy attempt to get up and just fell over again. It was pathetic. This sleek, clinical, killing machine that his best friend had become gasping and writhing on the wet ground.

Rogers knelt down. Bucky threw a pitiful punch at him. Rogers wrapped his arms around Bucky's torso.

"Go to sleep, Buck." Bucky clawed ineffectually at his arm, kicking at thin air. "It's OK, it's over now, just go to sleep." Rogers didn't move. Bucky's struggles got weaker as the drug kicked in fully. Bucky was genuinely terrified of him. He didn't know him, still. There was still that nagging fear in the back of Rogers's mind; what if Bucky didn't come back? He had to believe he would. He had to try until he couldn't try any more. It had been hard for Bucky coming out of HYDRA the first time, after a matter of weeks. It had been seventy years this time, who knew what they'd put him through to make him like this. Bucky's movements were repetitive now, his eyes were still open. He looked more like a dying man than a man falling asleep. The medics knew what they were doing, the drugs hadn't done Rogers any lasting harm in testing.

"Bucky?" Rogers shifted slightly. Bucky didn't react. He was out. They'd done it. They'd subdued him. He looked up at Stark. "He's under, take him back to the chopper." Stark knelt down and let Rogers help him pick Bucky up so he wouldn't fall. "Just go. Get the arm off him, the rest of us can take this."

"Sure." Stark took off. Rogers looked over his shoulder, watching Stark fly in to the night. He had to turn his back on Bucky again, just for a little while. He was no use to him right now. He needed a medic to keep him stable and Stark to disarm him, literally, in case he came to as wild as he had been just then. No matter what, it would be easier to subdue him with one arm. If it came to that.

He looked round at Romanoff. She was crouched in cover to his left.

"Barton," He said in to radio. "We're going to fight our way up to you, then we all go through the place together. Stay put."

"Copy." The sound of a helicopter taking off came out of the darkness, taking Bucky back. They were alone with whatever was left of this HYDRA base. They could take it. There had to be thirty dead HYDRA on the ground outside. He signalled to Romanoff to follow him and charged the door.

Two things:

One, I don't write in chapters, so the breaks will be irregular and sometimes a little jarring. I do my best

Two, any and all reviews by actual humans gratefully received, even if you're tidying up my punctuation