Manipulations, betrayals, twists and turns... the Marseille Research Section Investigation Unit team is an elite unit experienced in all types of situations. Intervening under the leadership of Albertini on the most complex homicides in the Marseille region, Saint-Mathieu, Bérénice, Malo and Paulin also have a hard time with their own colleagues and their hierarchy. And Chapelle, one of them apparently, doesn't make it easy for them...