Very, very (seriously, very) loosely based on Hans Christian Andersen's fairy tale "The Snow Queen," this adaptation centers around princesses/sisters Anna (the voice of Kristen Bell) and Elsa (Idina Menzel). They're best friends and one of them, Elsa, possesses an unusual gift: she can make everything turn to ice and snow. The wrinkle? She can't always control her power. After a series of unfortunate events that turn the siblings into functional strangers, Elsa's strange magic turns debilitating curse, plunging the entire kingdom into a bitterly cold snowscape, one that could destroy the population. She flees and Anna enlists the help of mountain man Kristoff (Jonathan Groff) and a clueless talking snowman named Olaf (Josh Gad, who doesn't overwhelm the film as much as the trailer would suggest) to right all wrongs and bring her sister back home.