After breaking up with her boyfriend Ben, Michelle drives away from New Orleans. While in rural Louisiana, she hears news reports of blackouts in several major cities before she is sideswiped by a truck and knocked off the road, falling unconscious. Michelle wakes in a locked room within an underground bunker, her wounds tended to. Howard, the bunker's owner, tells her he brought her there for her protection, claiming that the air outside has been poisoned by nuclear or chemical fallout from an unknown force.