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My Heart Keeps Beating

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Steve likes to think Tony and he are starting to get over their initial bump at the beginning. He likes to think the banter and the snark are just parts of Tony Stark that Steve will eventually grow fond of. He likes to think Tony takes care of himself better now that Steve is around to help, that they’re all around to help. He likes to think Tony understands that ‘team’ means backup. He likes to think these things.

But he’s usually let down.

The latest explosion rocks the street, blowing out the bottom windows of the department store that Natasha is tucked up beside. The glass cuts over her cheek and she fires her gun toward the Doom bot bearing down on her. Steve throws his shield and it cleaves off its head, winding the bot down. Natasha nods at him in thanks and Steve turns, a bot clanking into place before him, when he hears a shout.

Iron Man pelts by, a strange beep making the robots roll after him furiously, until one of them fires a blast that takes out a repulsor boot. Tony goes down hard and Steve’s already running, cursing a blue streak as he leaps a car. When he gets close enough, he catches sight of thirteen bots with their lasers pointed at Iron Man, and Steve’s breath freezes in his lungs. He leaps forward but he’s too late.

Steve shouts out a warning and the bots fire, hitting Iron Man in the chest with a brilliant crackle. Iron Man takes it, the lights in his eyes flickering off momentarily before lasers cleave through all thirteen, effectively ending the battle. Steve feels his breath come back to him and he’s shoving the bots out of the way, unable to tear his eyes away from the melted metal around Iron Man’s chest, the ghastly flicker of the arc reactor strangely worrying.

“Tony!” Steve calls, kneeling down beside him. He’s furious and impressed and he wants to pick Tony up and shake him. Tony shakily sits up himself, shoving up the faceplate with a grimace. He smiles up at Steve, brilliant and manic and painful and Steve suddenly wants to gather him in his arms and never let go. He instead helps him to his feet.

Tony winces but, with Steve’s help, makes his way out of the ring of bots. Clint and Natasha are waiting for him, Clint catching Tony’s hand in a high five. The Hulk is bouncing one of the bots like a basketball, tossing it up to Thor who hits it with Mjolnir back at him. Steve calls for them to assemble so they can return to the Helicarrier for the latest debriefing.

Steve keeps an eye on Tony all through the ride back, noting how he’s favouring his left side, fingers a static motion over his thigh. Steve wants to ask, wants to know, but Tony is in a deep conversation with Clint over the use of acid arrows and how bad an idea that is. They return to the Helicarrier and Tony disengages the armour, it sticking to his chest momentarily before sliding off, revealing the black clad bodysuit. Steve catches Tony when he stumbles, worry creasing his brow.

“Are you sure you’re okay?” he asks.

Tony looks up at him and grins, but it’s wrong on his face. “Yeah. Yeah, I’ll be fine. Just need to run down to the lab for a hot minute.”

Before Steve can respond, Fury walks by, eye narrowed at the group of them. “Debrief, room seven. Now.”

Struggling to stand up straight, Tony meets Fury’s glare. “I just need to run down to the lab, just a small moment really, and I’ll –”

“You most of all, Stark,” Fury snaps, and waits till Tony is walking away from him, before following. Steve bites at his lip and throws off his cowl, following the rest of the team into the room. Tony drops into one of the chairs, face surprisingly pale. Steve catches the seat across from him as Fury starts in.

The meeting escalates when Fury brings up Tony’s disregard for orders, how he took down thirteen bots without notifying SHIELD or the rest of the Avengers. Steve finds his initial worry for Tony overflowing, and suddenly he’s in a shouting match with the man, leaning over the table to get as close to Tony as he can. Tony gives as good as he gets, shouting nonsense about time and equations and Steve wants to shake him again.

“You can’t be that reckless! Who knows what those bots could’ve done to you? Taking those kinds of risks will get you killed,” Steve snaps, his fingers curling in his gloves. Tony’s face pales momentarily before colour blossoms high in his cheeks.

“And you think that I would risk my own head like that? I understood the risks, Rogers, I understood the math, and I’m sick of this third –” Tony chokes off, eyes going wide, and his hand slams against the arc reactor.

The arc reactor that has gone dark.

All the colour leeches from Tony’s face as he crumples to the floor, catching his shoulder on the chair as he falls. Steve leaps over the table, Clint already kneeling at Tony’s side and panicking as he tries to keep Tony’s eyes on him. Steve falls to Tony’s other side, removing Tony’s fingers from the arc reactor and Tony makes a pained noise, thrashing as his eyes squeeze shut. Steve thinks he hears the word ‘Obi’ but he’s too busy screaming for someone to do something, anything, and Natasha is on the phone and Bruce is taking calming deep breaths and Thor is hovering just over Clint’s shoulder, and Steve can’t think over anything but the arc reactor dark and Tony’s fingers squeezing against his own.

Natasha shoves at Steve’s shoulder, getting in Tony’s face. “Tony! Tony, pay attention to me, come on now, listen up, can you hear me?”

Tony shudders out a breath and nods, eyes manic. Natasha’s voice is tightly concealed distress. “Pepper says you have more of these. Where are they? How can we get to them?” There’s a tiny voice emitting from the phone clutched in Natasha’s hand and Steve realizes who she was talking to. The doors slide open behind him and the med team comes barrelling in.

Another breath hiccups over Tony’s lips. “Lab. Code: Assemble-Captain-Iron. Fourth from right. Hurry.”

Steve’s up before the last word is out of Tony’s mouth, shoving one of the med staff out of the way as he trips over his feet. He bypasses the elevator as he takes the stairs, launching himself over the railing as he falls a good thirty feet, landing with jarring impact. He ignores the crackle in his bones and slips into Tony’s lab on the Helicarrier. The lights flicker to life and he can hear Jarvis whir up with a confused whine.


“Jarvis! Where is Tony’s safe, the one with his arc reactor replacements?” Steve asks, frantic. Jarvis clicks.

“Behind the portrait of the Iron Man suit, Captain.” Jarvis’ voice wavers. “Has Sir fallen in need of one?”

“Yes. Yes.” Steve rushes over, sending the picture clattering to the ground. The outer wall clicks open and a keypad slips into view. He types in the code Assemble-Captain-Iron and the safe snarls open, nine arc reactor replacements in view. He grabs the fourth from the right, slamming it closed again before rushing out. The lab darkens behind him as he takes the stairs up, clicking on his communicator.

“Natasha. Location?”

Natasha voice crackles to life. “Med bay, sector four. Hurry.”

The time is too long; he’s running scenarios behind his eyes even as he slams open the door, the med staff jumping at his arrival. He probably looks manic, desperate, and one of the staff points him over to the rest of the Avengers. Steve cradles the reactor in his hand as he approaches, and the paleness of Tony’s face, the rasp of his breath fighting to escape from his lungs, turns Steve’s stomach. He’s shaking so hard the reactor clinks against his armour.

“We’ve removed the old one,” Natasha says. She has the phone pressed to her ear. “Pepper says to attach the magnet to the bottom plate in the center of his chest. His body will do the rest.”

 Steve carefully moves the replacement over Tony’s chest, swallowing at the large hole that has taken up residence in the place Tony’s heart should be. He can’t breathe past the fear in his throat and he doesn’t know what he’s doing, but his fingers just manage to attach it and Tony sucks in a deep breath, eyes wide in pain and uncertainty and the reactor doesn’t light up, doesn’t do anything, and then his eyes slide closed and he falls limp on the bed.

Understandably, the Avengers panic. Bruce Hulks out, the Hulk reaching out to touch Tony’s limp hand with his green fingers. Clint clutches at the sheet that covers Tony’s legs and Natasha lets the phone fall from her ear in shock. Thor turns away. Steve can’t move, can’t think, can’t breathe. No.

And then Tony breathes in again, his entire body shuddering as the arc reactor shines to life and he’s coughing, doubling over with both hands pressed against his chest. When he looks up, he smiles crookedly at them all, sweat on his brow and colour coming back to his face.

“Who died?”

Steve, who couldn’t stop the swell of emotion from restarting his own heart if he tried, leans forward and presses his lips against Tony’s temple, reaching to wrap Tony up and press him close. He can breathe again, can think again, and Tony stills against him. He then seems to sag, folding into Steve like he belongs.

“Sorry. Didn’t think it was that badly damaged.”

“Do that again and I’ll shoot you,” Clint says, having stepped back. The Hulk leans forward, picking up Tony’s free hand with one of his fingers.

“Don’t,” he growls, and Tony smiles shakily at him.

“Sorry, big guy. Won’t happen again.”

Natasha brings the phone to her ear again. “He’s fine, Miss Potts. Yes, he’ll be getting a round scolding from all of us. Yes. Yes. Goodbye.” And then she pins Tony with a look. “You know not to do that again.”

Tony ducks his head against Steve’s shoulder and Steve doesn’t want to let go, knows how this looks, but he couldn’t care less. He runs a gloved hand over Tony’s hair and sighs out a breath. Tony seems to realize where he is then.

“Uh, Cap, as comfortable as this is, I think the med staff want to poke at me.” Tony tries to pull away and Steve stubbornly holds on. He sneaks in another quick kiss to Tony’s temple before stepping back, trying to force the blush from deepening in his embarrassment. Tony stares at him in wonderment and then the medical staff swarm and the Avengers are forced back and out. Clint leads a still worried Hulk from the room, Thor helping him with the task. Natasha sidles up beside Steve and raises an eyebrow.

“I know,” Steve says, and Natasha quirks her lips.

“As long as you're sure.”

He catches sight of Tony as the staff poke and prod at him, and knows it’ll be okay. After all, Tony may not realize the team is behind him, that the team cares, but Steve will change that.

And this, this, won’t happen ever again.