Nathalie Perros, a young female fire brigade officer, was shot dead during an intervention in a difficult neighbourhood. At first, suspicions are focused on Tony Serrano, a young man from the city, known for having assaulted firefighters in the past. However, the judge explores another much more delicate track: that of the young woman's colleagues. Alice Nevers is indeed certain that the murder was premeditated. Two men at the Saint-Marc barracks find themselves in the judge's sights: Sergeant Armandin, an officer with a shady temperament who could have killed Nathalie out of professional jealousy, and Major Roissy, head of the rescue center who seemed to harbor a tenacious resentment towards the victim linked to a personal tragedy.
