In the depths of the Basque country, a series of gruesome murders shakes a small village to its core. The investigation leads Inspector Amaia Salazar back to her hometown, where she must confront the dark secrets of her own past in order to uncover the truth behind the ritualistic killings. As the body count rises and the killer's presence becomes more ominous, Amaia must navigate a web of superstition and deceit to catch the elusive serial murderer known as El Basajaún.