Dr. Holden (Dana Andrew), a psychologist knowledgeable about the occult, is dismayed by a friend`s strange death, leading him to investigate a demon-worshipping cult in England. But the leader of that sect, Prof. Karswell (Niall MacGuinness), resists Holden`s inquiries by calling up an actual demon to fight the good doctor. Can Holden hold his own in a battle of good vs. evil? Based on the M.R. James short story Casting the Runes, Jacques Tourneur`s film is considered to be one of the true classics of the horror genre, relying heavily on the power of suggestion to create a heavy atmosphere of fear and dread. The famous, much-debated monster was added by the studio against Tourneur`s wishes. The original, uncut version is known as NIGHT OF THE DEMON.