During the Mexican Revolution, Reynaldo, a lonely antisocial man who lives isolated in the countryside, is tormented by a sinister creature that comes from the darkest depths of the forest. Pursued by his own past, Reynaldo, accompanied by Ramón, a young boy who is in his care, will confront the beast before it finishes them off. However, a dark and cold secret hides in the origin of the creature, because not everything is what it seems.