Paul Meurisse

Stanilas Octave Seminario aka 'SOS', détective

Micheline Francey

Muriel Pescara, the daughter

Gilbert Gil

Charles Pescara, the son

Pierre Renoir

Doctor Gérard Pescara, the father

Jean Tissier

Guillaume

Pierre-Louis

Paul Wantz

Junie Astor

Hélène Tassin, nurse

Jean Debucourt

Doctor Vermeulen

Jean Brochard

Investigating judge

Mady Berry

Brigitte Tassin

Pierre Palau

Doorman

Arthur Devère

Lock keeper

Marcel Pérès

Road mender

Sinoël

Gardener

Georges Bever

Baptiste, clerk

Madeleine Suffel

Hotel boss

Michel Seldow

Illusionist Pablo

Marc Arian

(uncredited)

Léon Arvel

(uncredited)

Alfred Baillou

Man (uncredited)

Rivers Cadet

(uncredited)

Marcel Charvey

(uncredited)

Raymond Destac

(uncredited)

Pierre Duncan

(uncredited)

Cécile Eddy

(uncredited)

Henry Gerrar

Concierge (uncredited)

Claire Gérard

Concierge (uncredited)

Colette Mareuil

(uncredited)

Pierre Moncorbier

(uncredited)

Geneviève Morel

Pescara cook (uncredited)

Henri Niel

(uncredited)

Julienne Paroli

Gossip (uncredited)

Marcelle Rexiane

Director (uncredited)

Maurice Salabert

(uncredited)

Germaine Stainval

Gossip (uncredited)

Jean-Marc Tennberg

Agent on duty (uncredited)

Georgette Tissier

Telephone operator (uncredited)