Directed by Cyril Frankel | Starring: Stewart Granger, Brigitte Horney, Eddi Arent, Susan Hampshire

A Scotland Yard detective is investigating a string of robberies and a murder, and the information he uncovers leads him to the estate of a wealthy but strange English family, who share their mansion with a group of nuns. The detective comes to suspect that neither the family nor the nuns is quite what they seem to be.

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