Slim Callaghan investigates the theft of the famous Upper Sangha diamonds. Disguised as a Salvation Army auxiliary, he boards a luxury yacht where a transvestite party is being held. During an ...

Slim Callaghan is sent to investigate the theft. But his tracks soon lead him to the welcoming skies of the Côte d'Azur. There, he decides to infiltrate a network of aristocratic spies.