It develops that Mrs.Von Sturm's late husband was found guilty of war crimes and the family's multi-million dollar estate seized by the Allies.

Four murder victims were a part of that Allied War crimes tribunal, and they may have illegally seized the industrial empire for themselves, which would give the Von Sturm family good reason for personal vengeance.

Inspector Holloway, who at times can seem like the only sane man in London, doggedly pursues the case to a successful conclusion...and salvages the romance of Louise Saville and her Number One Suspect fiancé, Donald Loftis, a medical student with the presumed technical knowledge to commit the murders.

[4] Robert Bloch recalls in his autobiography being taken with his wife to the country in England by Ronald Kirkbride, and "the next morning a limo took us to Shepperton Studios, where we lunched after watching Freddy Francis helm a scene for The Psychopath.

Or rather, it begins as a whodunnit – with the jong murder sequence of the opening being followed by the Inspector's visit to a quit, oldfashioned salon where three members of a string quartet gravely indulge in Mozart while awaiting their colicague – and gradually shifts gear until it blossoms into a fully-fledged horror film.

Much less flashy with his camera than usual, Freddie Francis is content to let his scenes speak for themselves ... Much of the pleasure comes from a really splendid cast, with Margaret Johnston enjoying herself hugely as the crazy widow, and Patrick Wymark much less mannered than he has been of late.