Murder in Batz(Les blessures de l'île)

The murder of a woman in an abandoned house is the first murder this rural French island has had in 100 years. Or is it? A cop who left the island 20 years earlier and a young intern who moved away when she was six years old - but doesn't remember those first six years of her life - team up to solve the murder and some other mysteries that develop during the course of their investigation.