In a Paris suburb, Moussa Jebli, a successful cannabis trafficker, sees his shipment seized by the drug enforcement authorities. His whole family is swept up in his downfall, including his younger brother, Driss, a brilliant student who has always kept his distance from the family business. Opposite them, William, a newly transferred young cop, discovers the rules of the police game.

Moussa's arrest has set the neighborhood on fire. William realises the consequences of his actions and tries to redeem himself in the eyes of his colleagues. Driss finds himself threatened by his brother's creditors and turns to his childhood friends to find a solution. In prison, Moussa has to deal with old acquaintances.

William confesses to his colleague Taz that he has been duped by his informant. They decide to follow him, only to find themselves in Driss's path. Forced to sell the cocaine stolen in the robbery, the young student begins dealing at Parisian parties, under the reproachful gaze of his girlfriend Inès.

The Jebli family heads to Morocco to win back the trust of their uncles, who produce the cannabis in the Rif mountains. William and Racheton, the head of the drug squad, are hot on their trail. But political intrigue thwarts the plans of both the police and the dealers.

Thanks to their alliance, Driss and William rise to power in their respective circles. William shines in the drug squad, making one record seizure after another, creating jealousy between the various law enforcement services. Driss is flooding the market with his product, while his clients are dropping off one by one. Left in the dark, Moussa becomes suspicious of his brother's spectacular rise.

Driss, blinded by his hunger for revenge, has finally managed to track down Benali. But following Moussa's information, the Customs raid his home. Racheton and William are compromised and will do anything to protect themselves. William must now go all the way to arrest his former ally.