He'd half been expecting her to call him on it, tell him he's talking crazy, and suggest he march back to HQ to get a full workup immediately; the narrowed eyes and tense movements don't faze him.

He nods.

"You remember that other me you met? The -- Stephanie Rogers?" he asks, a shallow line forming between his brows. It's still weird to think about. "She came from another, alternate universe, right? Maybe that's what's happening here, I-I don't know. I'm not crazy, Natasha."

He pauses, looking her in the eye with all the seriousness he can muster, before he continues. "But my best friend is on that ship. Bucky Barnes. And I can't leave him, not again."

Not like I did last time.