While vacationing, a girl and her parents are taken hostage by armed strangers who demand that the family make a choice to avert the apocalypse.

Anna, Elsa, Kristoff, Olaf and Sven leave Arendelle to travel to an ancient, autumn-bound forest of an enchanted land. They set out to find the origin of Elsa’s powers in order to save their kingdom.

When the newly crowned Queen Elsa accidentally uses her power to turn things into ice to curse her home in infinite winter, her sister, Anna, teams up with a mountain man, his playful reindeer, and a snowman to change the weather condition.