Le Voyou (1970)
Directed by Claude Lelouch

Film Synopsis

Escaped convict Simon Duroc evades capture by the police by ducking into a cinema and getting a woman he has never met before to kiss him.  The woman offers him a temporary refuge in his home and he gratefully accepts.  Simon's one thought is to take revenge against the person who caused him to be sent to jail for kidnapping a child.  Before doing so, he looks up his former mistress Martine and his criminal associates.  He will need their help if his private vendetta is to succeed.  It all began five years ago, when Simon conceived a brilliant plan to extort a large sum of money from a humble bank employee, Monsieur Gallois, by abducting his little boy.

By posing as a radio announcer, Martine was able to convince Gallois and his wife that they had just won a fortune, to be presented to them at a special ceremony at the Olympia.  Simon insisted on taking the Gallois' son away with him so that he could be made ready for the presentation.  It was the easiest abduction ever, and naturally Gallois' employers were more than willing to stump up the ransom money for the boy's release.  But after his son had been returned to him, unharmed, Gallois demanded a share of the ransom, and when he didn't get it he denounced Simon to the police.  It is a betrayal that has rankled in the kidnapper's heart ever since.  Now, with the help of his friend Charlot, he intends that Gallois shall pay dearly for his indiscretion...