A psychiatrist is summoned to treat the main suspect in a series of brutal sex crimes. Marco (Frank Cuva) denies committing the murders, but he has vivid dreams of each killing, and while the police are confident of his guilt, they don't have enough physical evidence to arrest him. With hopes of extracting a confession, Dr. Alden (Kenneth Montaigne) hypnotizes his subject and plumbs the depths of Marco's depravity, but the cause of justice is subverted by the psychiatrist's own unhappy marital situation. Before turning his patient over to the police, Alden plants a suggestion in Marco's subconscious, and the doctor's alcoholic wife is targeted as the next victim. If the concept of brainwashing another person into committing murder sounds familiar, The Psycho Lover makes no apologies for copping the idea. In a bold display of cinematic thievery, the psychiatrist is inspired when his mistress recounts the plot of a film she watched on television the night before: The Manchurian Candidate. The construct of the psychiatrist's love triangle is flimsy and laughable, but what's remarkable about The Psycho Lover isn't its logic. There are few films with horror sequences as visceral as these, and while genuinely frightening, they're a challenge to enjoy. Director Robert O'Neil succeeds all too well with his hallucinatory rape/murder scenes, bathing his sets in odd flashes of multicolored light as the nylon-masked maniac forces himself upon actresses who convincingly fight for their lives. The juxtaposition of these brutal dream sequences and the soap operatic plot is jarring, and the whole thing is iced with a god-awful soundtrack of flat, sticky love ballads. O'Neil debuted as a director with The Psycho Lover, and he'd go on to create the classic cult "teenage hooker" melodrama Angel in 1984. A strong constitution is required to enjoy the merits on display here; the reader can accept this as either a warning or a challenge.