Lise and Clovis find a third corpse in a state of decomposition in Annecy. The woman, assassinated according to the same ritual, was probably the killer's first victim. Meanwhile, Marianne's nursing assistant Marthe is corresponding with a man on a dating site who is actually the killer. As the case gets more complex, Lise discovers that Clovis has been lying to her about his frequent absences and decides to confront him. And their friend and neighbor Laure is getting harassed by a terrifying man.