Set in the 18th century, this French swashbuckler centers on Lagardere (Jean Marais), an adventurer whose life is affected when he decides to help out a nobleman in distress. Lagardere's comic companion Passepoil (Bourvil) adds a light touch to the proceedings. But when the nobleman is vilely murdered by a villainous courtier, Lagardere is duty-bound to raise the victim's little daughter as though she were his own. Time goes by, though not enough to erase the memory of the murder from the adventurer's mind. He decides to disguise himself as a hunchback in order to be accepted into the faction that had the nobleman killed, and from the inside as it were, plots his revenge.