Todd, a haunted young man, struggles to protect the innocence of Benny, his mute kid brother, in a post apocalyptic world where all the adults turned to zombies by a recessive gene. The gene continues to activate in the remaining feral kids as they reach adulthood, causing a short and vicious life span.

After a group of wayward teens at a wilderness boot camp break a strange 'orb' in the middle of the desert, they begin to experience attacks from a ruthless blood-sucking alien. With no chance of rescue, and nowhere to hide, they decide their only chance for survival is to fight for their lives.