After being implicated in a murder, a young woman flees New York City and moves to Los Angeles, where she rents a room from a writer. They begin an affair, but it seems she's been followed by a homicidal duplicate of herself.

When someone tries to murder watchmaker Eddy Kay, the incident triggers a barrage of nightmares and flashbacks into a past that isn't his own. Fearing for his sanity, Eddy contacts psychiatrist Dr. Anna Nolmar for help. Anna thinks he's hallucinating until another attack proves the dangers are all too real. The two of them go on the run, trying to discover the truth about Eddie's past and true identity before it kills them.