Rise of the Guardians

The story begins with the spirit of winter, Jack Frost being raised from a frozen lake, but he returns to the world unseen by people and it is learned that he cannot be seen because he is not believed in, and all of his memories from his former life are gone only his name; given to him by the Man in the Moon who rose him, is known to him.

300 years later, North receives a vision in his workshop of the boogeyman Pitch Black, and alerts the other Guardians; the head of the tooth fairies Tooth, the short tempered Australian-accented E. Aster BunnymundSandy to the North Pole. Upon their arrival, they do not want to believe that Pitch poses a threat, but their guide the Man in the Moon suggests otherwise and instructs them to induct Jack Frost as a new Guardian to combat the threat. Meanwhile, Jack instills fun and laughter in children from his childish nature and inspires a snowball fight between a young believer named Jamie and the local children, but still they do not believe in him and he is still invisible. Jack is taken forcibly to the North Pole by North's Yeti workshop workers, but declines joining the Guardians as his centuries-long isolation has left him bitter to the responsibility they hold dear to protect the children of the world. North tries to convince him otherwise, but they are alerted to an attack on Tooth's palace. When they arrive, they discover Pitch's nightmares taking all of the childrens' teeth and the baby tooth fairies that work as Tooth's assistants. Jack saves one before they are confronted by Pitch, who states he intends to stop the childrens' belief in the Guardians so he instead is believed in, wielding a power like Sandy's to turn his dreams into nightmares. Pitch escapes and the loss of belief in the tooth fairy seems to immediately effect Tooth. Jack volunteers to help when he discovers that the teeth provide the memories of the children they came from including his own and seeks to find his place among them. They manage to collect the teeth in one night and faith in Tooth is restored though they are caught by Jamie who can see them all with the exception of Jack. Jack and Sandy are attacked by Pitch's nightmares and though Jack's efforts are valiant, Sandy is overcome and seemingly destroyed by Pitch. With Easter a day away, the group agrees to help Bunny distribute his eggs. They find Jamie's toddler sister Sophie at the Warren and manage to decorate eggs for distribution, Jack then takes Sophie home. and the gentle, non-speaking

Lured by a familiar voice calling to him from under a bed in the forest, Jack and Baby Tooth discover Pitch's hideout. Pitch offers Jack's canister of memories in exchange for remaining a neutral party, but Jack refuses and in retaliation, Pitch destroys all the eggs before they make their way to the surface, destroying the childrens' belief in the Easter Bunny. Being blamed for the failure, Jack leaves the Guardians and isolates himself in Antarctica where he encounters Pitch again who offers a partnership to spread fear to all the children. But Jack wants to be loved, not feared and rejects Pitch's offer again. Pitch holds Baby Tooth hostage for Jack's staff, then reneges when Jack turns it over. Breaking the staff and sending he and Baby Tooth into a crevice with no escape, Baby Tooth suggests Jack open his memories, where he discovers he was a teenage boy who had saved his sister from falling through thin ice by alleviating her fear with fun, in turn though he'd fallen in, but that sacrifice inspired the Man in the Moon to resurrect him as Jack Frost. Inspired by this, Jack returns to save the last light of belief on Earth; Jamie. Not only does Jack succeed in reaffirming Jamie's faith in the Guardians, but he also instills a belief in him, allowing Jamie to see and hear him, much to Jack's delight. The other woefully weakened Guardians join Jack to face off against Pitch, and Jamie has his own friends join in the seemingly impossible fight; but their faith is more than a match for Pitch's nightmares and also causes Sandy's resurrection, which sends Pitch running. No longer feared, Pitch cannot be seen or heard by the human children, and his fear turns his own nightmares against him, dragging him back under the bed.

Jack accepts his place with the Guardians and says goodbye to Jamie and his friends, their hope renewed and their belief strong Jack assures Jamie that they are now in his heart and as long as they believe the Guardians will always be there to protect them.

Source: wikipedia.org