Sam and Molly are happy together and deeply in love. Walking back to their new apartment after a night out at the theatre, they encounter a thief in a dark alley. Sam is murdered and finds himself trapped as a ghost. He realises that his death was no accident. He must warn Molly about the danger that she is in. But as a ghost, Sam can not be seen or heard by the living, and so he tries to communicate with Molly through Oda Mae Brown, a psychic who doesn't believe in her own abilities or that her powers are real.