Diana Dalton, an underprivileged college student, learns about the Zombie virus outbreak six hours in advance. She uses this info, empties her savings, and teams up with top student Leo Lee to take over the school's supermarket, transforming it into a fortress. As the apocalypse progresses, she fends off Zombies and battles human nature. She discovers she is 'Patient Zero,' the only one with the antibody to the virus, holding the key to ending the apocalypse.