For a time Natasha settles for that. She wouldn't say she's content with it, though Steve's presence helps. He's solid. Familiar. Dependable. It's been a long time since Natasha really felt safe—maybe she never really has?—but she thinks that Steve's about as close to reassuring as she's likely to come.

There's no need to speak. That's comforting too. She doesn't have to pretend she's not waiting for something to happen, either the door to unlock or the incentive that Steve mentioned.

As it turns out, they don't have to wait that long, though. Minutes later, less than half an hour, a quick line of pain draws itself across Natasha's back, just under her shoulder blade. She tries to hold the reaction in, keep it quiet. It doesn't hurt that much. But she doesn't entirely keep from tensing. A flinch that barely twitches her face but tightens her shoulder.