Brigadier Stéphane Ruiz is a young and light-heartened cop who moves to Paris to be closer of his little son after the divorce of his wife. Working in the impoverished suburb of Montfermeil, in the 93th district, where Victor Hugo wrote his famous 1862’s novel “The Miserables”, Ruiz joins the local Anti-Crime Brigade, being paired with veterans but unscrupulous colleagues Chris and Gwada, who are charged with the task to train Ruiz about the way Montfermeil’s works and the people to meet. However, his first day in Montfermeil twists in bad way when the owner of a circus and his men meet where drug-lord Le Maire (“The Mayor”) claiming for a stolen baby lion a few hours ago, blaming him by the theft. Avoiding a fight between Le Maire and circus’ owner, the three cops patrol the hood looking for the animal, learning that a troubled kid named Issa is the thief, who stolen to have it as pet. But when Ruiz, Chris and Gwada locate Issa to recover the baby lion, Issa’s friends attempt to liberate him from the cops. With the situation out of control, Gwada shots a rubber ball just when Issa tried to escape and hits him in the face, just in the moment that all they realize that a drone of a boy named Buzz recorded all the incident. Patrolling around, Chris and Gwada locate Buzz and start a prosecution to catch him after to learn that drone’s card is gone. Hiding in a downstairs, Buzz escapes from Chris and runs to ask refuge to Salah, a Kebab’s owner and leader of the each time more powerful Muslim brotherhood in the hood. While Issa’s friends run to advise Le Maire about the drone and the record, Ruiz, Chris and Gwada moves where Le Pince (“The Clamp”), a bar’s owner in addition to Le Maire’s rival and Chris’ partner in business, looking for help, at the same time that Ruiz goes to a pharmacy to heal Issa’s hurts. But when a confident alerts about Buzz’s location, Le Maire, the cops and Le Pince meet at the same time at Salah’s local claiming by the card, not measuring the consequences of their acts.