During World War II, four siblings, Peter, Susan, Edmund, and Lucy Pevensie, are evacuated from London to escape the Blitz. They are sent to live in the countryside with Professor Digory Kirke. While exploring the large, mysterious house, Lucy, the youngest, stumbles upon a wardrobe in a spare room. Venturing inside, she finds herself in a snowy forest. This forest is part of a magical land called Narnia, which is inhabited by talking animals and mythical creatures. Lucy returns to tell her siblings, but they do not believe her until they all end up in Narnia together through the wardrobe.

Upon their arrival in Narnia, the children discover that the land is under the curse of an eternal winter imposed by the White Witch, Jadis, who proclaims herself queen. The inhabitants of Narnia reveal a prophecy that four humans will help to end her tyranny. The siblings meet several Narnian creatures who guide and help them, including Mr. Tumnus, the Faun, and the Beavers, who tell them of Aslan, the great lion and true king of Narnia. As the children embark on their journey to find Aslan and join forces with him, they learn of their destiny to help free Narnia from the Witch's reign with the guidance and support of its magical inhabitants.