Captain La Reynie is an ambitious man. He works for Minister D'Argenson, who is given the task to catch Cartouche. La Reynie arranges so that his sister Juliette marry D'Argenson. In her way from the convent to D'Argenson, Cartouche kidnaps Juliette for ransom. In Cartouche's lair, Juliette sees that The Regent is not what she thought to be, that people is hungry and poor, and that Cartouche is loved by the people. After D'Argenson pays the ransom, Juliette is set free, but she and Cartouche fall in love with each other.
D'Argenson finally succeeds in capturing Cartouche, but his enemy, Prime Minister L'abbé Dubois, sets Cartouche free in secret. The Regent is angry that he delays the marriage between D'Argenson and Juliette and that D'Argenson can forget his ambition to be Prime Minister.
The new law makes the people exchange their silver/gold coins for paper money. Gold pours to The Regent, who then move the treasure to one of his castles. On the way, the soldiers who is transporting the gold, led by La Reynie, is attacked by Cartouche and his gang. The gold is taken, half is for the poor, half for Cartouche and his gang, who have decided that the attack is their last job and they will all start a new life. Humiliated, La Reynie (played by Grégory Fitoussi, who is so sympathetic in Engrenages. Here he plays the enemy, but when he is hanged under the bridge and people throw anything to him, I feel sorry for him.) commits suicide, while The Regent takes everything from D'Argenson (money, land, title, etc).
Juliette returns to the convent, where Cartouche visits her and takes her to start a new life with him in Canada.
One of Cartouche's gang betrays him, but another member of the gang claims that he is Cartouche. A few people has seen him and not many who know what he looks like. Father Dubois visits him in jail and states that the man is Cartouche and this is the man who gets the death punishment on the wheel in Place de la Grève.