There's not a single scary moment in this boring albeit well made Hammer entry. Christopher Lee is an excommunicated priest who somehow manages to promise to give the Devil a daughter. Richard Widmark is the hack horror novelist trying to stop him. The idea of teaming these two famous screen baddies is promising, but they share scant screen time together. A dubbed Nastassja Kinski plays a young nun and Denholm Elliott is her father, who tries to renege on his deal with Lee. It's a lousy movie all around and even manages to wastes Honor Blackman (as Widmark's sharp tongued literary agent). Based on the (presumably better) novel by Dennis Wheatley, this film surely exists solely to cash in on the EXORCIST craze of the early 70s.