When the zombie apocalypse hits the sleepy town of Little Haven - at Christmas - teenager Anna and her high school friends have to fight, sing and dance to survive, with the undead horde all around them. Teaming up with her best friend John, Anna has to fight her way through zombified snowmen, Santas, elves and Christmas shoppers to get across town to the high school, where they'll be safe. But they soon discover that being a teenager is just as difficult as staying alive, even at the end of the world.