Harry Potter and the Dragon Trainer

Harry and Ron have discovered Hermione's secret to getting to all her classes. A Time Turner! Hermione shows them how it works, but it malfunctions and sends them hurtling backwards through time. They land in on a island swarming with Dragons and Vikings, and must figure out how to survive and get back to Hogwarts with their new friend Hiccup, and his dragon Toothless.