There isn't time to make many plans; Snow can't be allowed to complete his project. And in the end, there's little information to work with anyway; they know practically nothing about Snow's fortress save its location, which is deep enough into Axis territory that the Army can only hope to send the smallest force to infiltrate it. There will be no supporting battalion of infantry this time.
To allow so small a force to overcome so great an obstacle, Beetee quickly synthesizes a powerful explosive. He teaches Gale how to set and detonate the charges, any one of which could bring a Schloss down on the heads of those inside, provided that it's placed in the very heart of the castle, near one of the central load-bearing pillars.
Peeta wanted to be the one to carry the charges, to let the others cause a distraction for him. But the top brass at the Army nixed that immediately. Their plan is that Captain America leads one team to cause a distraction, Gale and a few guards take advantage of the chaos to plant the charges. That first team might be able to escape the blast but there's little chance of the second team making it out alive. To the Army, it's a simple proposition; they have millions of ordinary privates but are still unable to produce a second super soldier. Besides, who could cause a bigger distraction than Captain America?
Two nights before the mission, Peeta wants, no, needs to talk to Gale. But for once in his life, words don't come easily to him. They sit in silence at the table until Peeta asks "Gale, why'd you volunteer?"
Gale laughs a little. "Why'd I join the Army? How do I even tell? Because I'm a red-blooded American boy and I want to kick Adolf Hitler right in the seat of his pants. Because the Army pays more than the mines and being here means mom can afford milk for Posy. Because I'm nineteen and I'm not crippled so it's not like Uncle Sam was going to give me a choice anyway."
Of course they both know that isn't what Peeta meant. He and Gale stare into each other's eyes for just a moment before Peeta says "I don't see how you're going to make it out after those charges are set."
It's a morbid conversation but Gale smiles in reply. "You know any other guy in your position would shake my hand and say bon voyage. But you can't, can you? You're worried about how she's going to take it."
"She loves you. She can't just-"
Gale shakes his head violently. "She's going to have to! Did you ever win one of those chess matches of yours without sacrificing a piece? This is war; if I have to bring that wreck down on my own head, I'll do it. I'd expect the next guy to do the same."
Peeta can tell that Gale's telling the truth, but there's an image he can't get out of his mind. "Just like your father."
Gale nods casually. "My old man and Katniss' died for nothing, spent fifteen years breaking their backs in a mine because they didn't see any other way and then died for nothing. But this is different. This war could change things. People seeing some 'redskin' like me in Army; that could change things."
Peeta nods absentmindedly. He can see the soundness of the Army's plan; to them, Gale is their least valuable piece. But there's another move on the board.
He considers trying to talk to the others about it, but he knows they wouldn't accept his plan. So instead he waits until they're on the plane that will drop them within a few miles of the castle. Unlike the others, he's already wearing his parachute; but they don't think anything of it, he's always going out of his way to be prepared.
They're taken completely by surprise when he casually gets up, takes the small satchel of explosive charges, shoves an envelope into Katniss' hand. She only has a few seconds to look at him questioningly before he opens the door and leaps into the sky.
He waits until the exact right moment to pull the parachute and as he gently floats down to the earth, he imagines her reading his letter.
I hope you can understand why I'm doing this. I don't want any of you to die in my place. This is what I was meant for; I can reach the center of the castle and bring it down. This was entirely my decision and I don't want any of you to blame yourselves. The rest of you all have someone back home who needs you. No one needs me.
But it's all limited to his, admittedly vivid, imagination. Because Katniss never read the letter. She dropped it in favor of her parachute as soon as she saw him open the door and eight seconds after he jumped, she followed him.
He makes rapid progress through the snow-covered trees, slowed only when he encounters more of Hydra's creatures. At first they appear to be unusually large wolves; but wolves don't rear up on their hind legs and gesture to each other. They fight with an almost human intelligence but their tools are limited, eventually Captain America leaves a pile of them, dead or unconscious, behind him. Twenty minutes later, Katniss gives them a cursory glance before continuing to follow his trail.
He climbs the walls of the castle with amazing agility and descends on the garrison from the roof like a winter storm, striking and moving on before the patrols of guards can respond. And his plan seems to be working, he descends further, moves closer to his target; he's actually considering planting the charges when he stops suddenly. There's a guard slumped in the corner with an arrow sticking out of this chest.
He can follow her trail by the sounds of alarm, dropping the satchel, he barrels through the hallways until he finds her pinned down by submachinegun fire. He defeats her opponents easily, but it takes time. By the time it's finished, he's fighting from atop a pile of white uniforms.
Katniss hugs him tightly, but after they're each assured that the other is safe, she pulls back and hisses "That was a great job obeying orders, Captain America."
"Maybe they'll cashier me and I can die as Peeta Mellark."
"And that's your plan? To die heroically?" she asks with her voice breaking.
"Katniss, the Army's plan was for Gale to die down here. He's got his whole family to look after! My parents, my brothers, sure, they'll be sad, but they'll get over it. They don't need me."
"I need you!"
He tries to protest but she silences him with her lips. For a time they lose themselves in the feeling of being so close to each other. The sensations are new to both of them, this hunger that only grows worse as they feed it; even in the drafty halls of stone, they feel almost unbearably warm.
They pull apart suddenly when they're started by the sound of thunder off in the distance. Without discussing it, without any idea what they'll do when it comes time to plant the charges and at least one of them must die, they continue on. Because they have to, because the mission is too important, because they're both dead anyway if they don't keep moving.
In the end, they don't even get a chance to argue about it. They step through a doorway to be confronted by a veritable firing squad of men with rifles trained on them. And just behind them a harmless-looking old man who inclines his head and asks, "Now my dear Mr. Mellark, you aren't going to be difficult are you?"
When Peeta shakes his head, Snow continues "I thought not. No one who worked so diligently to save her would throw her life away with both hands. You know I really am quite grateful for your desire to shield her. I'm not at all certain that my men could have overcome you alone. The people we love can be our greatest burdens; we will do things for their sake that would otherwise horrify us."
They are bound and taken deeper into the fortress. Peeta spends the entire trip thinking about breaking his bonds and catching their captors by surprise, but the MP-40 submachine guns trained on him and Katniss stay his hand. When they reach a large and gaudily-decorated office, Snow addresses Captain America.
"They must have told you that Aurelius was my student. You know I was as shocked as anyone when his formula produced you. Unfortunately, my attempts to reproduce that haven't been any more successful than your own people's. There must be something unique about your blood chemistry…" He shakes his head, as if he woke from some daydream. "Pardon me; genetics is such a fascinating subject for me."
Peeta eventually grows impatient with this monologue. "You could have killed us before. What do you want from us?"
"How very direct, your Dutch blood comes to the forefront. What I want, Mr. Mellark, is the exact location of each of your organization's bases here in Europe. I'm afraid that our aerial surveillance has been somewhat curtailed in recent years. But I'm sure that this won't be difficult for you, they say that you have a remarkable memory."
"And if I refuse?"
Snow gives them a sickening smile. "Well, I think you will find that I'm prepared for every eventuality." He instructs his men to raise Katniss above a pit of flaming coals. "It's so obvious, you know, your infatuation with this mongrel amazon of yours. And being burned alive really is the most terrible way to die. I'm quite certain that you won't let that happen."
So is Katniss and that thought burns her more painfully than any fire. She wanted nothing more than to help Peeta and now he might give up everything that he'd fought for to save her. But as Peeta hesitates, the winch lowers her and she finds that her suit protects her from the worst of the fire. She puts on a great show of moaning in agony, but Peeta, who knows every sound she makes better than anyone, can easily tell that it's all an act.
As Snow grows impatient, his breathing quickens and the stench of blood fills the room. The winch lowers her until she can stir the coals with the toes of her boots, tongues of flame licking up her suit. The idea springs into her mind fully formed in an instant; she moves one of the coals onto the tip of her right boot while keeping up just enough of the act to divert any suspicions. Then, when Snow angrily turns to face her, she kicks the flaming coal directly into his face.
It bursts apart on impact and Snow's entire head is briefly shrouded in flame. Katniss can see the entire gruesome spectacle, with the flesh burned off, the blood and muscle are drawn so tautly that his head appears to be nothing but a red skull.
His minions forget about everything else as they try desperately to save him. He's clearly beyond any help but they refuse to accept that. Without the guns trained them, Peeta snaps his bonds and yanks Katniss down and away from the flames. A split-second after this registers with the guards, he's knocked them out with a blow a piece.
His shield and her bow are on Snow's desk where he was admiring them, but they can't find the satchel of explosives so easily and they have to keep moving. They pass through a maze of stone-arched hallways but don't dare stop to try to orient themselves; somewhere further down there must be some way to end the work Snow began. In the confusion they work their way through the halls until they stumble onto the laboratory. Quickly Peeta douses the floor with organic solvents and sets them alight. The noxious smoke filling the air only adds the confusion as they make their escape.
They flee up to ground level, unsure of which exit to try until they hear familiar voices off in the distance. When they make their way through the smoke-filled halls, they find Boggs, Mitchell, Holmes, Finnick and Gale subduing some of the disoriented Hydra guards.
Finnick greets them with a smile. "Well thank God you avoided the worst of the smoke. I wasn't exactly looking forward to giving you mouth-to-mouth, blue-eyes."
They move quickly after that, escaping the castle before any more of the wooden support beams go up in flames. The plane that brought them over lies in a small valley not far away. Thanks to another of Beetee's feats of engineering, it can take off with only a grassy field for a runway, spiriting them back from behind enemy lines.
They can hear the thunder of anti-aircraft guns off in the distance as Peeta remarks "It's going to be a rough ride." Katniss straps herself in next to Peeta as if she thinks he'll jump out again. She grips his hand tightly in hers, turns to him and pleads with soft eyes, "Stay with me."
Without a second's hesitation, he replies "Always."
To the world, the story that follows this one is that of Captain America and the Mockingbird and their service to their country during and after the war. But there is another story behind that public façade; that of the life Peeta Mellark and Katniss Everdeen, later Mellark, had together when they weren't wearing costumes. The story of how they dealt with the horrors of war will never find its way into a USO poster, but to those that knew them best, the story they didn't share with the world is the only one that really mattered.
Years later, their children are asleep down the hall but she can still hear the echoes of those anti-aircraft guns in the nighttime thunder. The scene repeats itself, as it has countless times before; she clings to him and whispers "Stay with me". She's not awake enough to hear his response, but she doesn't have to be, it never changes.
Notes: I had a hard time getting from Peeta jumping out of the plane to the confrontation with Snow; the "action" scenes just don't come naturally to me. Getting them from the laboratory to the end of the story wasn't much easier. I decided against an epilogue chapter, but this looks like the perfect set-up for an "Avengers" style sequel including Peeta as Captain America, Katniss as Mockingbird, Beetee in a powered Iron-man suit, Finnick being granted the powers of Neptune by a magical trident and Johanna has a former spy in a catsuit with trust issues as "The Victors". Hopefully I'll get some work done on my canon fics before I end up writing that.