In this Spanish comedy-drama, a man befriends his wife’s lover in an attempt to understand what has happened to their marriage and win her back.

Santi, a young high-school student with a serious physical reaction to sunlight, is forced by his health to move with his single mother to a shadowy, isolated village in the mountains of Spain where the inhabitants begin to reveal themselves as strangely xenophobic. When terrible, violent events begin to occur, Santi becomes first a pariah at school and then strongly suspected by the police of hideous murders. Santi himself, however, wonders if he is not the next victim.