There's an old, old ache that pangs at Bucky's words, at the look on his face. They've talked through it, and it's been so long, but there are times when Steve is right back there on the train, staring at the yawning chasm below, feeling so desperate the only thing that kept him from pitching himself off to follow was the mission they had to complete.

He'd let it happen once. Never again. Never again.

He waits until Bucky looks to him, then nods, firmly. "We won't stop," he says. "We'll find out what happened. And we'll bring her home."