The Chronicles of Narnia, #1: The Lion, the Witch & the Wardrobe
Four adventurous siblings—Peter, Susan, Edmund, and Lucy Pevensie— step through a wardrobe door and into the land of Narnia, a land frozen in eternal winter and enslaved by the power of the White Witch. But when almost all hope is lost, the return of the Great Lion, Aslan, signals a great change . . . and a great sacrifice.
Book order in suggested reading order (publication).