The wildcard Labroukos (1981)

An unbeatable gentleman, he meet a widow, owner of a nightclub that has a hidden casino in its own. He goes in the club, plays cards and wins at first. But when he starts to lose large amounts, he understands that he has been the victim of gamblers. His reaction is immediate, he takes lessons from professional gamblers, and avenues his opponents. In the end, he also wins the beautiful widow.