Charlie and Pete, two American backpackers in Mexico, make their way to the town of Santana after their bus breaks down. There, a fellow American named Sam, who bartends at a local restaurant, warns them that the townspeople will all leave the area before sundown. This is because the town was cursed by the devil, who, for one night per year, gets to take over the village with his legion of demons and capture any humans who remain present, sending them to eternal torture in hell.