Lisa and Julien are married and lead a happy uneventful life with their son Oscar. But their life radically changes one morning, when the police comes to arrest Lisa on murder charges. She's sentenced to 20 years of prison. Convinced of his wife's innocence, Julien decides to act. How far will he be willing to go for her?

In Marseilles, the discredited and alcoholic Detective Schneider hijacks a bus and forces the bus driver with a gun to drive him home. He is arrested by the swat force and his washed up career in the police department practically ends. Schneider is removed from the investigation of a serial-killer that is committing hideous crimes against women and assigned to a bureaucratic work in the night-shift in the precinct. Through glimpses from his recollections, Schneider recalls the tragic accident that killed his daughter and left his wife attached to a life support system. Meanwhile, the sick criminal Charles Subra, who killed the parents of two girls many years ago, convinces the probation committee in the prison that he has found God and is regenerated and may be released. Justine, one of the daughters that survived, has never overcome the trauma of her loss and is worried with the possibility of the freedom of the criminal...

In the underbelly of the Parisian criminal world, the Police are frustrated by a gang committing a series of violent robberies. Leo Vrinks and Denis Klein are two cops seeking promotion, and the imminent departure of the Chief sets the scene for them to compete for the vacant throne. The competition between them becomes increasingly ruthless and blurs the usual lines of morality, until there seems no difference between the police and the criminals they chase. Vrinks, meeting with a source, becomes involved with a murder. Klein seizes the opportunity to up the ante and arranges for the arrest of Vrinks, but when he goes further and viciously involves Vrinks' wife, Camille, revenge is inevitable.

A cop goes up against his lifelong friend, who has become one of the city's biggest drug traffickers.