A teacher writing a book about gambling meets a hotel/casino owner threatened by a gangster.

A middle-aged playboy becomes fascinated by the daughter of a private detective who has been hired to entrap him with a client's wife.

Steve Gordon, an American agent posing as a black market operator, is in Tangier on a mission to stop the plans of three atomic-scientists who are there to pool their secrets and sell them in a package to the Communists.