Detective John Hobbes is searching for a criminal he's already met... already caught... and already killed.

Homicide detective John Hobbes pursues a killer down a bustling sidewalk. There she is: a small, middle-aged woman. No wait: the killer is the timid man beside her. Now it's someone else. It's all and none of them. Because the murderer Hobbes seeks is a demon passing from one host to another with a brush of an overcoat or touch of a hand.