a disc jockey on air, only to find it was a pre-recorded show. They come across another survivor there, Hector Gomez, who spent the night in the back of his steel truck. When Sam talks into the microphone, she is heard by researchers in an underground installation out in the desert. As they listen to Reggie, Sam and Hector debate what to do, the scientists note that the zombies, though less exposed to the comet, will eventually disintegrate into dust themselves. Hector leaves to check if any of his family survived, but promises to return as soon as possible. Reggie and Sam then go shopping for guns and clothing at a mall. After a firefight with some evil stock boys, the girls are taken prisoner, but are saved by a rescue team sent by the scientists. Reggie is taken back to their base. Audrey White, a disillusioned scientist, offers to dispose of Sam, whom she diagnosed as having been exposed to the comet due to her developing rash, and to wait for Hector to return. After she fakes euthanizing Sam by injecting her with only a sedative, she kills the other remaining scientist. When Hector returns after an encounter with a zombie child, Audrey briefs him on the situation and then gives herself a lethal injection (as she herself has been exposed). Sam and Hector set out to rescue Reggie. Back at the base, it is revealed that the researchers had suspected and prepared for the comet's effects, but inadvertently left the ventilation system open and the fans running during the comet's passage. The deadly dust permeated their base. Reggie, who has become suspicious, escapes and discovers that the dying scientists have hunted down and rendered healthy survivors brain-dead. They harvest their untainted blood to keep the disease at bay while they desperately search for a cure. Reggie saves a young boy and a girl before they are processed, then unplugs the other victims from their life support machines. Sam and Hector arrive and rescue the trio and blow up the scientists. Eventually, rain washes away the red dust, leaving the sky clear. Reggie pairs up with Hector, and they assume parental roles with the kids. Sam feels left out. Frustrated, she ignores Reggie's warning about crossing a deserted downtown street against the still-operating signal light, claiming there is nobody else left. Sam is almost run over by a sports