At the hospital for her ultrasound appointment, Morgane is called to a crime scene: Dr. Bubé has been murdered with a fire extinguisher in his office. The crime scene is chilling, given the violence depicted in the images on site. The investigation takes a strange turn when the team discovers that anti-speciesist activists are involved. Morgane will have to unravel the mystery of this murder alongside Karadec, who is preparing to leave the force, and Commander Prigent, her successor. A task that matches her abilities but appears much more complicated than it seems.