Married French lawyer Andre defends succesfully the case of Yvette, who committed a robbery. He falls in love with her, but she isn't true to him.
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.
A Russian spy is sent out to steal sensitive information from NATO about military mobilization. Without much intelligence of his own, the distrusted agent of Soviet intelligence needs all the help he can get from his "talented" partner Penelope Lightfeather as they scatter around the French countryside for secret rendez-vous' while trying to avoid being caught by counter intelligence agents and distrustful communist operatives.
