Moments before his capture by police, a thief digs a grave to hide a bag of money. Released from prison years later, he returns to retrieve the bag, only to find a shrine to an unknown ...

Toledo, Spain, 1997. The residents of Río Blanco have accepted the settlement of Moroccan seasonal workers in Fuensanta. Coexistence brings tensions, known by Sonia, an NGO leader; Father Ángel, the local priest; and Safir, the imam. What they don't imagine is that Fuensanta's foundations hide something capable of unleashing their worst nightmares, regardless of their beliefs or prayers.

Four childhood friends are reunited when one of them surfaces after twenty years, forcing them to confront a creature straight out of a spine-chilling Moroccan legend.