Investigating the murder of a street artist, Cannes detective Camille Delmasse keeps running into the suave but shady Harry King. Meanwhile, Camille's father, the former chief of police, is set to be cleared of corruption until secrets upend events.
When a casino owner's wife is poisoned, suspicions fall on banned gambler Roxie Roland; Camille turns to Harry for help - who better to bring down a con woman than a con man? He discovers the name of the man threatening Camille's father.
A murdered monk is found on the island of "the man in the iron mask" fame. Camille is trying to understand her father's decisions while Lea has a decision of her own to make.
Camille visits her father in prison despite efforts to intimidate her. Ordered to protect a visiting billionaire who has received death threats, she and Lea turn to Harry for intel about a legendary assassin known as the Nightshade.
When Pascal Fontaine is found hanged after a séance, seemingly the victim of a curse invoked by a family matriarch's death in an asylum; the team deal with shady mediums and scorned lovers, while Harry and Camille set a trap for Boire.
The death of an actress's assistant during the Cannes Film Festival could be an accident or murder - affecting Lea deeply. With his daughter at risk, Harry decides to stop Boire once and for all, but what he learns will devastate Camille.
