A young Parisian, Pierre Marsais, visits a Champs-Elysées movie house to see Crime Does Not Pay , a film based on three celebrated crimes. The first part, THE MASK, concerns a 15th-century Venetian duchess, Dona Lucrezia, who invites her unfaithful lover, the Chevalier Giraldi, to what will be his own funeral and then has him murdered. The duchess pays for her crime when her maid, who secretly loved Giraldi, coats the beauty mask she wears at night with acid. In the second episode, THE HUGHES CASE, Clovis Hugues, a radical member of parliament, becomes involved in a scandal when his wife, Jeanne, is unjustly accused of being the mistress of Monsieur Lenormand. In reality, Madame Lenormand had hired a detective, Morin, to find proof of her husband's infidelity so that she can obtain a divorce, and Morin had invented the evidence. Jeanne sues Morin for libel, but Morin wins an acquittal by bribing the jury. Jeanne then takes the law into her own hands and shoots the detective. At her own trial for murder, she is vindicated by the courts. The third segment, THE FENAYROU CASE, takes place in 1913 and concerns Gabrielle Fenayrou, an adulteress who maneuvers her aged husband into killing Aubert, a lover who plans to marry another woman. She then betrays her husband to the police so that she can enter into a new affair with his young doctor. The two toast their love from a bottle of poisoned wine the husband had prepared for Aubert. In the final episode, THE MAN ON THE AVENUE, Marsais leaves the theater at the end of the film and is fatally injured in an automobile accident. The driver of the car, an American colonel, calls on Marsais' widow, an alcoholic. A subsequent investigation reveals that Marsais, aided by his mistress Hélène, had been plotting to kill his wife.
