Win Tickets to see the new Disney film Frozen

Frozen is in cinemas from 26th of December and to celebrate we're hooking you up the chance to win tickets to see it!
The Competition

What is the Fairytale that frozen is based on?

Email your answer with your contact details to win@bigscreennz.com by Thursday the 26th of December 2013 (Please put "Frozen" in the subject line)
The Premise
Anna, a fearless optimist, sets off on an epic journey - teaming up with rugged mountain man Kristoff and his loyal reindeer Sven - to find her sister Elsa, whose icy powers have trapped the kingdom of Arendelle in eternal winter. Encountering Everest-like conditions, mystical trolls and a hilarious snowman named Olaf, Anna and Kristoff battle the elements in a race to save the kingdom. From the outside Anna's sister, Elsa looks poised, regal and reserved, but in reality, she lives in fear as she wrestles with a mighty secret-she was born with the power to create ice and snow. It's a beautiful ability, but also extremely dangerous. Haunted by the moment her magic nearly killed her younger sister Anna, Elsa has isolated herself, spending every waking minute trying to suppress her growing powers. Her mounting emotions trigger the magic, accidentally setting off an eternal winter that she can't stop. She fears she's becoming a monster and that no one, not even her sister, can help her.