Peter Lawford stars as Nicholas Revel, a jewel thief who is mistaken for a serial killer of London police officers. To clear himself, Revel has to catch the real killer. An improbably plotted, cliche-ridden, mildly entertaining mystery with Lawford as his usual handsome, debonair, bland self. Not much action except for an effective fight between Revel and the murderer at the film's climax. The cast wanders through a foggy, gaslit studio set that looks like it was left over from a Sherlock Holmes film. This sort of story has been done worse, but it has been done better, too. Mostly it has been done too often.