Spies from several countries try to find out what secrets are hidden in the mind of a young amnesiac girl who has appeared in Paris.

To inherit his uncle's immense fortune, Frédéric must divorce his wife with of course all the wrongs against her. He unsuccessfully tries the "love strike" and ends up employing a detective to help him find the fault of his decidedly too embarrassing wife. An idea comes to him: his wife is a fan of naturism.

The director of the French Ministry of the Interior summons Serge Cazals, an Interpol agent, to unmask the leaders of an organization that sells military intelligence and has just made a name for itself with the assassination of Secret Service ace Georges Dandieu. Cazals is soon spotted by his adversaries and dangerously threatened. Through an intermediary in the organization, he obtains a telephone number that leads him to various leads, but to no avail. He then decides to set a trap, with the help of his friend Violaine.