Bucky holds the tent flap for her, then enters after her and comes to attention with a brisk salute. "Captain Rogers. Agent Carter."

"Carry on, Sergeant." He can tell that Steve knows something's up. He'll never understand how the other man knows him so well, except that he knows him the same way. "What is it?"

"Mr. Stark has asked Agent Carter and myself to report to the field where Agent Carter arrived tonight for an experiment intended to secure her transport home," he reports, and doesn't let himself look anywhere but at Steve.