In the second episode of "La Caza. Monteperdido," Lieutenant Santiago Baín and Sergeant Sara Campos know they are in Ana's hands. The girl, who has returned after five years of kidnapping, is all they have to figure out what happened. However, Ana's testimony provides little information. She can't identify her captor, as he always wore a mask. The officers' work focuses on trying to locate the hideout where they were held hostage and where they suspect Lucía still is. Throughout this search, Santiago and Sara will realize that the man they are looking for is someone from the town itself. Perhaps someone very close to Ana.

Lieutenant Baín and Sergeant Sara Campos are managing to piece together the years of Ana and Lucía's kidnapping. They learn more and more about the kidnapper and better understand the hell the girls suffered. However, Lucía's parents, especially Joaquín, are not willing to stand idly by. That's why they don't hesitate to use Ana to try to precipitate events and find Lucía as soon as possible. But one event marks a dramatic turn in the course of the investigation and in Sara Campos's life.