Having fortuitously discovered a photograph in which Marthe embraces someone unknown, Étienne Dorsay becomes jealous and imagines various stratagems to identify the lover. In the meantime, he and his friends acquire a weekend house for a very low price.

• Les Productions de la Guéville
• Gaumont International
• Jean Rochefort
• Claude Brasseur
• Guy Bedos
• Victor Lanoux
• Danièle Delorme
• Marthe Villalonga
• Jenny Arasse
• Josiane Balasko