Occult novelist John Verney (veteran American star Richard Widmark) has his hands full. He has to keep safe the daughter (Nastassja Kinski) of an associate (Denholm Elliott). You see, eighteen years ago Elliott made an unholy pact, and now the girl is intended for use in something depraved by heretic priest Father Michael Raynor (Sir Christopher Lee).

At the time, this was the final theatrical horror film for Britains' renowned Hammer Studios. It was actually pretty successful, but the studio was simply too much in debt to completely reap the benefits. Based on the novel by Dennis Wheatley, it's a commendably low-key, restrained film, with occasional moments of violence / gore as well as cheesiness. As directed by Peter Sykes, the film has the potential to bore some members of the audience, but it's generally got enough interesting material in it to make it palatable.

The cast provides the principal value. Widmark at first seems really out of place, but he does a solid job. Lee delivers what is one of his all-time best villainous performances for Hammer. The supporting cast is pretty eclectic: Honor Blackman, Michael Goodliffe, Eva Maria Meineke, Anthony Valentine, Derek Francis, Frances de la Tour, etc. However, many eyes will be on Kinski, in one of her earliest roles; she does convey an essential naivety and innocence, and the audience will automatically be on her side. Those who are interested should note that she has a controversial few seconds' worth of full frontal nudity near the end.

Although not on the level of another Wheatley shocker ("The Devil Rides Out") produced by Hammer, this does show its viewers a fairly good time, operating with its approach of subtlety. One problem, however, is the ending, which is over too quickly, and robs us of real satisfaction.

All things considered, Hammer could easily have signed off with a much worse horror film. This, at least, is generally compelling.

Seven out of 10.