Chance comer

one who comes unexpectedly.

See also: Chance

References in classic literature ?
With a single drop of ink for a mirror, the Egyptian sorcerer undertakes to reveal to any chance comer far-reaching visions of the past.
Our interview is not to be broken in upon by every chance comer, every impertinent guest--and there are plenty of such stupid, impertinent fellows"--(he bent over and whispered mysteriously, with a funny, frightened look on his face)--"who are unworthy to tie your shoe, prince.