The quiet routines of two couples are interrupted when someone in their circle of acquaintances is cruelly murdered; and then another murder follows as skeletons in many varieties—and even the Aztec Lord of the Underworld, Mictlantecuhtli—revel during the night of the Day of the Dead. What forces of evil have been unleashed in the community that is encroaching on the rugged Mountain Lion Canyon? Above the canyon hovers the scraggly large rock that was named La Roca, the new development in the foothills of the Santa Catalina Mountains. A mountain lion stalks the canyon and so do, it seems, human predators.