Con man Dudley Jerico sets out to rob corrupt millionaire Victor Rosso of his legendary Gemini diamond, but there's another operator in town who is out to con the con.

A scrying glass puts an antiques exporter in the path of a woman fleeing from devil worshipers and the evil hypnotist who leads them. Originally an episode of British horror anthology TV series, Hammer House of Horror, that later received a feature release in the United States.