Santi is 16 and suffers from a disease that makes him sensitive to sunlight - a fact that doesn’t make his or his mother Julia’s life in Barcelona easy. Santi longs to leave somewhere with minimum sunlight. After a lengthy discussion Julia decides to move to Arrozas de Valdeon - a remote village in northern Spain that is situated in a steep valley and therefore rarely penetrated by the sun’s rays. Instead of the mountain idyll they so long for, they soon find themselves in the midst of a nightmare. For there are strange goings on in Arrozas de Valdeon. At first, animals begin to disappear - apparently ‘usurped’ by something unknown lurking in the nearby woods. And it is just a begining...