Michel Simon as Albert Ménard-Lacoste / Alain Ménard-Lacoste

Louis de Funès as Emile, manvalet

Marguerite Pierry as Madeleine Lacoste

François Guérin as Pierre Lacoste

Laurence Badie as Geneviève Lacoste

Claude Gensac as Evelyne, chambermaid

Léon Walther as Maître Denisot, notary

Pauline Carton as Boss of the hotel

Marthe Salbel as Marie, cook

Lana Marconi as une prostituée, "la comtesse"

Michel Nastorg as Mechanic

André Brunot as Dr. Ogier

Georges Bever as Taxi driver

Max Dejean as Tavern boss

Marcel Pérès as Commissioner Vincent

Jacqueline Gut as Mercer

Jacques Derives as Doctor from Roubaix

Marcel Mouloudji as Singer

Marc Arian as Mr. Valembray, department head (uncredited)

Louiguy as Self (uncredited)

Christine Vall as Maid (uncredited)

Sacha Guitry as Self in the prologue / Narrator (uncredited)