The Pevensie children ~ Peter, Susan, Edmund, and Lucy ~ are sent to live in the country with an eccentric professor named Digory Kirke during World War II. The children explore his house on a rainy day and the youngest of the children, Lucy, finds a wardrobe full of fur coats. Lucy steps inside to hide from the other children and finds herself entering an unusual snowy wooded land.
Lucy passes a lamppost near the edge of the thick woods and then encounters a faun named Tumnus, who is surprised to meet a human girl. Tumnus explains to Lucy that she is in Narnia. Mister Tumnus invites Lucy to have tea with him. Lucy and Tumnus have a wonderful tea, but the faun gets upset, bursts out crying, and confesses that he is a servant of the White Witch, an evil woman who has enchanted Narnia so that it is always winter. Tumnus explains that he must capture humans for the White Witch. Lucy begs Mister Tumnus to release her, which he does, but not before the White Witch finds out about her visit. Lucy returns to the wardrobe to exit Narnia and tells her brothers and sister all about her adventure in the wardrobe. They think that she is making up the story. All three insist that Lucy was only gone for a few seconds and not for hours as she has told them. When the Pevensie children look in the back of the wardrobe they see that it is an ordinary piece of furniture.
Edmund teases Lucy about her imaginary world but one day when he sees her vanishing into the wardrobe, he follows Lucy and finds himself entering Narnia also. He does not see Lucy when he comes out of the wood, but instead encounters the White Witch that Tumnus had warned Lucy about. The Witch Witch introduces herself to Edmund as the Queen of Narnia and feeds Edmund enchanted Turkish Delight, which gives Edmund an insatiable desire for more of the sweet treat. The Witch uses Edmund's greed and gluttony to convince Edmund to bring back his siblings to meet her. On the way back to the lamppost, Edmund sees Lucy. Lucy tells Edmund about the White Witch. Edmund denies any connection between the Witch and the Queen. All Edmund can think about is his desire for the Turkish Delight. Lucy and Edmund return to Peter and Susan, back in Professor Kirke's country house. Lucy hopes Edmund will support her story about Narnia now that he has also visited there, but Edmund denies it all and tells Peter and Susan that it is a silly made-up story. Peter and Susan are worried that Lucy is insane so they talk to Professor Kirke. The Professor shocks Peter and Susan by declaring that Lucy is telling the truth.
One day the children all hide in the wardrobe to avoid the housekeeper and some houseguests. Suddenly all four Pevensie children find themselves in Narnia. Lucy leads them to Tumnus's home, but a note informs them that Tumnus has been arrested on charges of treason. Lucy knows that this means the Witch is aware that Tumnus spared Lucy's life, and that the Witch has now captured Tumnus. Lucy demands that her siblings help her rescue the faun from the White Witch. Along their way, they meet Mr. Beaver. Mr. Beaver brings them back to his home, where he explains that the children cannot save Mr Tumnus. The only thing they can do is join Mr. Beaver on a journey to see Aslan, a wise lion who is revered by Narnians. The children are eager to meet Aslan, except for Edmund, who is quite frightened at the thought. Mr. Beaver and the children make a plan to meet Aslan at the Stone Table the following day, but they realize Edmund has disappeared. Edmund has gone off searching for the White Witch to warn her of Aslan's arrival and of the Beavers' plan. The Witch is enraged when she hears that Aslan is in Narnia and immediately begins plotting to kill all of the children. The Witch is aware of a legend that says that four humans (sons of Adam) will someday reign over Narnia and overthrow her evil regime.
The children and the Beavers are on their way to the Stone Table, racing the Witch to arrive first. As they travel, they meet Father Christmas, who explains that the Witch's spell of "always winter and never Christmas" has ended. The spell causing the winter snow is broken as the snow begins to melt and the children begin to see signs of spring. The White Witch takes Edmund toward the Stone Table and he begins to realize what a fool he has been. Once spring arrives, the Witch can no longer use her sleigh, so she is stuck and does not arrive at the Stone Table before the children do. When the other three Pevensies meet Aslan, they are in awe, but they quickly grow comfortable around him. They trust him, despite their fear. Aslan promises to do all that he can to save Edmund. He shows Peter the castle where he will serve as king. As they talk, they hear Susan blowing the horn that Father Christmas had given to her, a signal that she is in danger and needs their help. Aslan directs Peter to go and help her. As he arrives, Peter sees a wolf attacking Susan, and stabs the wolf to death with the sword he received from Father Christmas. Aslan sees another wolf vanishing into the woods and hopes it will lead them to the Witch, so he sends others to follow the wolf. The Witch is just about to kill Edmund as the rescuers arrive. Aslan and his followers rescue Edmund, but are unable to find the Witch because she is in disguise. Edmund is so relieved when he sees his siblings.
The next day, when the Witch and Aslan speak, the Witch demands Edmund's life because she says Edmund is a traitor. The Witch declares that according to the Deep Magic of Narnia, a traitor life's is forfeit to the Witch. Aslan does not deny this, and he secretly reaches a compromise with her. The following night, Susan and Lucy both notice that Aslan has grown quiet and somber. The girls awake during the night and notice that Aslan has disappeared. Susan and Lucy go immediately to search for Aslan. When they find Aslan, he tells them they can stay until he tells them they must leave. Together, Aslan, Susan, and Lucy walk to the Stone Table, then Aslan tells them they must leave. Susan and Lucy hide behind some bushes and watch the Witch and her followers brutalize and kill Aslan. Aslan sacrificed his life for Edmund. Susan and Lucy stay with Aslan's dead body all night. In the morning, they hear a great cracking noise, and are shocked to see the Stone Table has been broken. Aslan has disappeared.
Suddenly Susan and Lucy hear Aslan's voice. Aslan has risen from the dead. Aslan carries the girls to the Witch's castle and they free all the prisoners who have been turned to stone, bringing them back to life again. Aslan, Susan, and Lucy meet up with Peter's army and join forces to fight the White Witch's troops. Peter and his troops are exhausted. Fortunately, Aslan swiftly kills the Witch and Peter's army then defeats the Witch's followers. Aslan then knights Edmund, who has repented for being in league with the Witch. The children are given their thrones at Cair Paravel, the castle in Narnia. Aslan subsequently disappears. The children live in Narnia for several years, eventually become adults. They reign over Narnia for many years. One day, as they are on an excursion, hunting for a magical white stag, they arrive again at the lamppost where the story began - the place that had marked the border between Narnia and our world. The Pevensies crawl back through the wardrobe to our world. No time has passed in our world, even though they had grown up while in Narnia for so many years. Once they return to Professor Kirke's house, they are children again. The four children tell Professor Kirke about their adventure, and the Professor assures them that they will return to Narnia again some day.
Quotes from The Lion, the Witch, and the Wardrobe by C.S. Lewis