Western Pyrenees, year 778. When his land is threatened by the ruthless armies of the Frankish emperor, a Basque warlord asks for help from his ancestral gods.

Based on a Basque folk tale, ”Patxi herrementaria,” collected by priest, archaeologist and anthropologist José Migel de Barandiarán in 1903, the story is set in the Basque region in 1845, in a universe inhabited by mythological diabolic creatures, battling to capture the souls of the unwitting.