A student opens fire for more than an hour on his fellow college students, and films the massacre on his cell phone. Rocher worries about not being able to find the crime weapon, but the end of the video shows the shooter being stopped by a professor, who then cold-bloodedly kills him with the weapon before running away. Why did this university teacher, who had already resolved the situation, suddenly turn into a murderer? Thus begins Chloe's analysis of one the most complex profiles she has ever faced. Meanwhile, Chloe meets a powerful businessman who asks her to help find his runaway daughter. Rocher continues his descent into hell with Volker, the perverse inmate who says he is willing to donate his kidney to save the life of Rocher's sister.
—Beaubourg Audiovisuel