A woman is stalked by a psychopathic killer. She eventually kills him, only for the man to show up again, this time sane and without any knowledge of the attacks. The police don't believe her, but one detective agrees to look into it.

In this adaptation of a novel by famous horror author Dean R. Koontz, the story follows Hilary, a journalist who becomes the target of a relentless, incredibly enraged and extremely violent psychopath bent on murdering her at any cost. After several nearly successful attempts on her life, she manages to recognize her attacker as Bruno, a man whom she once interviewed, but fails to understand why he would want her dead. Later, she manages to kill him in self-defense, but then he shows up again, this time seemingly sane and without any knowledge of any of the attacks. The police do not believe her story, but a detective named Tony sympathizes with desperate Hilary and agrees to help her investigate the matters further. They soon realize that Hilary is not losing her mind and that someone - or something - really is trying to kill her and that Bruno's past may very well be the key to solving this terrifying supernatural mystery.