Manuel Ortigosa, a Parisian writer, learns that Aymeric, his husband, is killed in a car accident near Aix-en-Provence. IN shock, Manuel immediately goes to the south of France, where he meets his in-laws.

After his husband's funeral, Manuel meets the members of his in-laws' family and their house staff. These meetings are a way for him to try to better understand Aymeric, who never spoke about his family.

Still upset by the message incriminating his husband, Manuel continues his investigation at the castle. The death of the youngest family member, Enguerrand, seems suspicious. With Richard, they enter into the family chapel, where Enguerrand died.

Richard is shot in the leg. Manuel thinks someone at the estate wants to hinder their investigation. Their investigation leads them to Anthony Laville, the young drug dealer whose fingerprints were found in Aymeric's car.

Richard and Manuel are convinced that Anthony's death is a new murder. They suspect the young man of having blackmailed Aymeric, who would then have attacked him to silence him permanently.

Jeoffrey is out of danger despite his suicide attempt. Richard and Manuel discover that he was in a relationship with Anthony. To Manuel's relief, their investigation proves that Aymeric was not responsible for the young man's death.