From the dark of everlasting damnation comes evil - to walk among the living!
An occult criminologist investigates a businessman who dabbles in the black arts while trying to survive against a powerful demon and an evil cult.
Screenplay: Gene Roddenberry, Samuel A. Peeples
Story: Gene Roddenberry
Director: Clive Donner
Producer: Gordon Scott
Director of Photography: Arthur Ibbetson