show one's face
Appear, as in She was so upset that we were sure she'd never show her face at the theater again. This idiom has appeared in slightly different forms, such as show one's neck or visage or nose, since about 1225.
show (one's) face
To make an appearance: Don't show your face on my property again.
show one's face, to
To appear, to be present. This expression generally implies that one is appearing, despite being embarrassed about something, or that one is afraid to appear for some reason. Thus Samuel Richardson used it in the early novel Clarissa (1748), “I should be ashamed to show my face in public.” It continues to be used in just this way.