Dr. Cordelier, living in a suburb of Paris, withdraws from society to pursue research into the functioning of the human brain. His lifelong friend, Maître Joly, becomes concerned when Cordelier draws up a will that bequeaths his entire estate to a stranger, Monsieur Opale; he cannot understand why Cordelier defends him, considering Opale attacks women and children. After a colleague is killed, Joly confronts Cordelier and discovers the truth behind his friend's behavior.
Producer: Jean Renoir
Screenplay: Jean Renoir
Director: Jean Renoir
Director of Photography: Georges Leclerc
Dr. Cordelier / Opale
Joly
Dr. Lucien Severin
Little Girl Attacked by Opale
Commissioner Lardaut
Inspector Salbris
Boss of the Short-Time Hotel
First Passer-By during the Aggression