When she was just a baby, Anna (Angharad Rees) witnessed her father, Jack the Ripper, murder her mother. Now a disturbed adolescent, she frequently falls into trances and continues Dad's bloody business. Psychiatrist John Pritchard (Eric Porter) believes that Anna can be cured. But the doctor's interest in her goes beyond the professional, and his burgeoning passion may be his undoing. Horror vet Peter Sasdy directs this Hammer chiller.