Having sex with her husband, Carole shouts Gabriel's name. But the couple does not have time to argue, because Jean-Louis receives a call. A fire ravaged a squat occupied by African clandestine makes a victim. Jean-Louis charges Gabriel and Carole with the investigation. The two investigators go to the scene of the tragedy. Five people were injured, including a woman who jumped from the first floor with her two children to escape the flames. Gabriel is convinced that this is an accident, although firefighters have noticed that the fire broke out in several places at the same time. For Carole, it's a crime .