La tête du client (1965)

Gaston Berrien ,a hatter in Vaucresson,spends some happy day with his wife Françoise, a detective stories writer ,and his children,Freddy and Evelyne .As his business is bad, he runs an illegal gambling den with his brother-in-law .Both accomplices make their fortune ,unbeknown to everyone.However , a blackmailer ,Joe,threatens to give the information to the police ,if they do not pay a hefty sum.They decide to do away with this pest.