Acid thunderstorms at the high school turn everyone into Zombies except senior Ralph and freshman Scott, who find their only solace is in a dank janitor's closet. With their teenage turned-undead-friends clawing at the door, who will make it out to spark the Resistance?

Newcomer Evan joins a group of teens on a getaway in Joshua Tree. While exchanging ghost stories around the campfire, Evan reads aloud a mysterious chant from an internet site. From that moment, someone--or something--is among them.