With Prom only hours away, the usual suspects of Cosa High (Cheerleaders, geeks, bad boys and the happy-go-lucky student council alike) are preoccupied with the annual rituals of teendom. On the night of the big dance when the dead unexpectedly rise to eat the living, polar opposite groups will be forced to unite in their final chance to save the town from the zombies.

Katherine Morrissey, a former Christian missionary, lost her faith after the tragic deaths of her family. Now she applies her expertise to debunking religious phenomena. When a series of biblical plagues overrun a small town, Katherine arrives to prove that a supernatural force is not behind the occurrences, but soon finds that science cannot explain what is happening. Instead, she must regain her faith to combat the evil that waits in a Louisiana swamp.