At the start of the movie, a young Diego is crossing illegally in to the United States from Mexico. Along the way, he meets an old Aztec man who tells him about a shortcut across a river. Before they get there, the old man performs an ancient ritual to the Aztec god of sacrifice and dies. Diego is then left alone at the river. Ten years later, Diego is living in East Los Angeles, California. He has a girlfriend Maria Somera and lives with his best friend Zak Silver. Maria's uncle, a priest of a local church does not like Diego's sympathy for the Aztec religion. This usually causes Diego and Maria to meet in secret. When a local Dia de los Muertos (""Day of the Dead"") festival is to take place, a celebration with Aztec roots, Diego becomes excited. He dresses as an undead Mariachi with the traditional facepaint. Unfortunately, he has to go alone because both Zak and Maria are busy the night of the celebration. While driving to the festival, Diego's car crashes and he is killed. He later wakes up in Mictlan, the Aztec land of the dead. There he is sacrificed in an ancient ritual by the god of death and sent back to the land of the living a year after his death. He later learns that the old gods want to rule their world again. Three sacrifices representing the Church that took away their power must be made. This puts Maria's life is at risk because she is a descendent of one of the first churches in Mexico. Now Diego must fight against the gods that made him to save the woman he loves.