35-year-old Audrey, the only survivor of a mysterious serial killer who raged in the Biarritz region 16 years earlier, is brutally taken back to her past by a new crime: a 17-year-old girl is found murdered on the Basque coast. Nothing links this murder to the series of crimes committed in the early 2000s by the “Itsas Killer,” but Audrey is certain that Itsas is back.