River's head snaps to the side, raking the room in a quick sweeping glance, and back to the target.

(And there, her first expression: a fleeting moment of what might be exasperation.)

Her fanning hand drops, slaps leather and jerks sideways all in one motion as she spins to set her back to the wall; the right-hand gun shoots for blood, and the left-hand one to splinter wood.