During WW2, a posh bourgeois woman (Morgan)is compelled to live under the same room as a crude simple-minded yet big-hearted man.(Bourvil) Her husband was arrested by the Gestapo and she is a hunted woman.

Mr. Joly, doctor Cordelier's lawyer, is amazed to discover that his client and friend leaves his possessions to a stranger, Opale, a sadistic criminal. He needs this man to prove that people's behavior can be adjusted at will...