When a disgruntled elf takes over the North Pole, she turns time backwards and Santa Claus begins getting younger fast. It's up to a loyal elf, a little girl with a magic key, and the now-teenage Santa to save the future of Christmas.

An apocalypse survivor defies the colony to seek help for a sick ex-lover, encountering an outside world of desperate humans and ravenous zombies while being forced to confront a past that haunts him.