Set in 1970s Chile, the story revolves around Jaime, a quiet and introspective young man who unexpectedly finds himself incarcerated for reasons that aren’t immediately clear. Inside the prison, he is plunged into a harsh reality governed by unwritten rules and dominated by power struggles among inmates. Jaime catches the attention of an older, influential prisoner named "The Stallion," who offers him protection. Over time, Jaime navigates his new environment, forming close bonds with other inmates while learning to reconcile his internal turmoil and the external violence of the prison world.

As Jaime adjusts to his new life, the film explores complex themes of desire, power, and survival within the oppressive confines of the penitentiary. The relationships Jaime forms inside prison both challenge and redefine his understanding of loyalty and love. Through various flashbacks, glimpses of Jaime’s past gradually unveil the circumstances leading to his imprisonment, offering a window into his psyche. The narrative carefully builds tension as it portrays Jaime’s transformation from a vulnerable outsider into a figure shaped by the brutal environment he inhabits. The portrayal of life in the prison underscores broader societal issues, creating a poignant backdrop for Jaime's personal journey.