Policía Foral inspector Amaia Salazar, a former FBI agent, lives in Pamplona with her American husband, James, an artist.

[3][4] Ainhoa was found naked and posed in the woods, her face scrubbed clean of makeup and her hair neatly arranged, and a cake placed on her shaved pubis, with her heels taken off.

Amaia links this with the death six weeks earlier of Carla Huarte, who was strangled with the same type of rope, and fears a serial killer may be at work.

Amaia's relationship is strained with her elder sister Flora, who, with Rosaura, now runs the family business, a commercial bakery.

Amaia instructs police officer Jonan Etxaide to look back 20 years for similar crime patterns and other events occurring in Baztan.

She believes she is looking for an older male who was likely sexually repressed in his youth and who would be familiar to the girls, making it likely they would go willingly with him.

The serial killer is dubbed El Basajaún ("Lord of the Woods") by the media after a Basque mythological creature.

Several weeks later, Flora's book, which she dedicated to her mother, was published, while Amaia and James reveal to Rosaura and Engrasi that they are expecting a child together.

[6] The film was produced by Atresmedia Cine, Nostromo Pictures and El Guardián Invisible AIE alongside Nadcon.