[ That's a start. Black Bolt stops as soon as the knife is out; not for fear for himself, but an attempt not to startle her any more than she already is. He spreads both arms, palms up, that universal I mean no harm. Then he shifts, one hand moving as if it would lie a palm flat against the door, were he close enough to it. And were he close enough to it, that hand would effectively prevent exit. He hopes she gets the suggestion. ]