Julio and Timoteo operate a private detective agency that specializes in cases relating to partners who cheat on their spouses.

When a vacationing couple in Tangiers runs into an old friend there, they discover that he is searching for his missing girlfriend who has been kidnapped by an international gang of white slavers.

A U.S. engineer (Tab Hunter) in Spain hunts thieves of two candlesticks, one of which is found in his suitcase.