Around 1750, in the Dauphiné not far from the Swiss border, a cooper, tired of the injustices affecting the peasants crushed by taxes, went into revolt. Louis Mandrin, a handsome fellow without fear and without reproach, puts himself out of the law by refusing to obey the local nobility. The public authorities are tearing their hair out because the man is elusive. Helped by his faithful friends and by two women in love, Mandrin will become a legend.