Finch, a photographer, doesn't really make a living from his business. One day, he meets his old classmate Mario, who works for a Senator whose daughter he married, Cléo. But Mario is no longer interested in his wife and he has a secret affair with her younger sister Ariane. Finch takes some pictures and he hopes to blackmail him in order to get money from the Senator. Mario asks Ariane for help. Finch makes Ariane pay, who learns the truth of the situation. To punish Mario, Ariane asks him to t...