Morgane returns to police work after a long break, although her strained relationship with Karadec continues to be a burden. A new case brings distraction: the up-and-coming rapper Naïma has been murdered. The investigation reveals that Naïma was working on a song about sexual abuse - a controversial topic that may have been her undoing.

Morgane and the team investigate the death of Adèle Mercier, a young mother who was executed with a targeted shot to the head. In the course of the investigation, it emerges that the unassuming victim led a dangerous double life, which may have been her undoing. As Morgane gets closer to the dark secret of the dead woman, her relationship with Karadec becomes increasingly unbalanced.