One day, Polly Plummer, a young girl living in a London row house, is surprised to meet a young boy, Digory, who’s moved in next door. He’s living with his old, unmarried aunt and uncle, the Ketterleys, because his mother is dying and his father is away in India. The two children speculate about Digory’s “mad” Uncle Andrew and Andrew’s mysterious study. Polly and Digory become friends and spend the summer exploring the interconnected attics of the row houses.
One day, the children accidentally stumble into Uncle Andrew’s study when they think they’re entering a neighbor’s attic. Uncle Andrew emerges from a chair and frightens the children by locking them in the room, then flatters Polly with the gift of a shining, faintly humming yellow ring. As soon as she touches the ring, she suddenly disappears.
When Digory demands to know where Polly has gone, Uncle Andrew tells him a story. His strange godmother, Mrs. Lefay—who was rumored to have had fairy blood and to have dabbled in dark magics—bequeathed him a little box. Breaking a promise, Uncle Andrew eventually studied magic himself and opened the box, discovering dust from another world. He used the dust to make magical rings—yellow ones to send his experimental subjects to another realm and green ones to bring them back home. Polly doesn’t have a green ring, so Digory realizes he’ll have to rescue her, since his cruel uncle is also too cowardly to do it himself.
After Digory puts on the yellow ring, he suddenly finds himself emerging in a light-filled wood with many small ponds. Polly is there, and despite both children being in a dreamy haze, they eventually remember what’s happened and make a plan to return home. At the last minute, they decide to explore other pools to see what kinds of worlds might exist there. The children switch to green rings, join hands, and jump into a different pool, which deposits them in a cold, ruined, apparently vacant world called Charn. They wander through crumbling courtyards until they enter a hall filled with the frozen forms of dozens of richly-dressed people. There’s also a little golden bell with a hammer beside it. After a heated argument (Polly senses danger and wants to go home; Digory doesn’t want to be driven mad with curiosity), Digory strikes the bell with the hammer to see what will happen. Moments later, a fierce, beautiful queen is awakened from her enchanted sleep and approaches them.
The Queen, Jadis, leads the children out of the building and surveys the ruins of her once-great kingdom, explaining that she destroyed Charn herself using a spell called the Deplorable Word, lest her sister wrest her throne away from her. She then cast herself into an enchanted sleep until someone someday came to ring the bell. When Jadis hears Digory mention that the children come from a different, younger world, she greedily demands to visit that world, so that she can subdue and conquer it. Though Polly and Digory try to flee homeward, they discover that the magic rings work like magnets—because the Queen is clutching Digory’s ear, she is accidentally pulled back to London with the children.
In London, the once-intimidating Uncle Andrew is dwarfed by Jadis and cowers as she demands that he find her a suitable chariot and rich clothing before she conquers this world. Digory and Polly wait helplessly at home as Jadis wreaks havoc throughout the city. When she returns to the Ketterleys’, she has commandeered a hansom cab and its hapless horse, Strawberry, and has a number of indignant merchants, angry policemen, and cheerful onlookers in her train. The Queen—now referred to as the Witch—attacks a policeman with the broken arm of a lamp-post. Digory and Polly manage to grab both the Witch and a yellow ring in order to get the Witch out of London, but they accidentally bring Strawberry, the Cabby, and Uncle Andrew along with them. This time, when they leave London behind, they all find themselves in a perfectly dark world, with the sound of beautiful singing in the distance. As this new world gradually fills with light, they see that the Singer is a huge, bright Lion.
The Lion’s singing has brought forth the stars, the sun, and now grasses and trees. The Witch hates the music and flees the Lion’s presence, but the children long to meet him. Suddenly, countless animals of different kinds burst forth from the ground. The Lion, Aslan, walks among the animals and touches noses with certain ones. The chosen animals gather around him, and he breathes into them the ability to think and speak. Aslan charges these Talking Beasts with the care of those who don’t speak.
Digory summons the courage to approach Aslan directly, on Strawberry’s back. Aslan asks him how the Witch came to enter Narnia, and Digory, compelled by the Lion’s expectant silence, confesses that he is responsible for releasing the Witch from her enchantment. Before dealing with Digory, Aslan speaks with the Cabby and summons the Cabby’s wife from her own world. He tells Frank and Helen that they will become Narnia’s first king and queen.
Then Aslan explains to Digory that he must undo the harm he’s done. Digory has been tearfully thinking of his sick mother, wishing Aslan could heal her, but he agrees to do as Aslan bids: to journey into the Western Wild to find a certain tree in a walled garden. He must pluck an apple from that tree and return it to Aslan. Aslan then transforms Strawberry into a flying horse, renaming him Fledge, and charges him to fly Digory and Polly to the garden. The following day, they arrive at the fragrant garden, and Digory enters alone. Digory reads an inscription on the gates: “Come in by the gold gates or not at all, / Take of my fruit for others or forbear, / For those who steal or those who climb my wall / Shall find their heart’s desire and find despair.”
Inside the garden, Digory quickly finds a silver apple. As he’s about to leave, he is startled to encounter the Witch. She, too, has taken an apple and eaten it, granting her immortality. When Digory tries to flee, she tells him that eating one of these apples would cure his mother—and even let her live forever. Digory wrestles with this terrible dilemma, but finally recognizes that the Witch is trying to tempt him and doesn’t really care about his mother. Still, he’s heartbroken, and it’s only the memory of Aslan that comforts him as he flies back with Fledge and Polly.
When Digory returns to Narnia with the apple, Aslan is pleased. He has Digory plant the apple on a riverbank. After King Frank and Queen Helen are crowned, everyone notices that an entire tree of silver apples has now sprung up. Its beautiful aroma is repellent to the Witch, who will stay away from Narnia for hundreds of years. Aslan reassures Digory that he did the right thing by refusing to take the original silver apple for himself, and then offers him another apple from the tree, which will heal his mother’s illness. Digory joyfully picks an apple and returns to his world with Polly and Uncle Andrew. Aslan also warns the children that their own world is susceptible to become a wicked, ruined realm like Charn, and that they must bury the magic rings so that no one else can ever use them.
Back home, Digory cuts up the Narnian apple for his mother. By the next day, she is feeling remarkably better, and within a month, she is healed of her deathly illness. Digory discovers that another apple tree—albeit not a fully magical one—has sprouted up where he buried the apple core in the backyard. He and Polly bury the magic rings at the foot of this tree.
After Digory’s mother gets well, his father returns from India with an inheritance, and the family moves to a country estate, where Polly comes to visit often. Narnia enjoys many years of happiness and harmony under King Frank and Queen Helen. In midlife, after Digory has become an accomplished professor, he inherits the Ketterleys’ London house. When the backyard apple tree is blown down in a storm, he uses its wood to build a wardrobe, which will become the gateway to later adventures in Narnia.
