Dorothy lives on a farm in Kansas with her Uncle Henry and Aunt Em. Except for Dorothy and her happy little dog, Toto, the people, buildings, and landscape of the farm are dry, gaunt, and gray. A cyclone roars across the prairie, but Dorothy and Toto do not make it into the cyclone cellar in time. Stuck in the farmhouse, Dorothy and Toto whirl up to the top of the shrieking cyclone. The cyclone carries the house for hours, and eventually Dorothy falls asleep.
Dorothy awakes with a jolt and sees sun shining through the windows. Her house has been set down in the land of Oz, a beautiful, verdant land, flush with gorgeous flowers and birds. Upon arrival, a group of little old men called Munchkins and a good witch called the Witch of the North approach Dorothy. The Witch of the North calls Dorothy a sorceress and congratulates her for killing the Wicked Witch of the East and freeing the Munchkins. Dorothy is mortified to realize her house has landed on the wicked witch, leaving only the witch's two feet sticking out. The Witch of the North gives Dorothy the witch's charmed Silver Shoes. Dorothy asks for help returning home to Kansas, but the Munchkins and good witch say it is impossible, for there is a great desert surrounding the land of Oz. Dorothy begins to cry, and so do the Munchkins. The good witch balances her cap on her nose and says, 'One, two, three,' and the cap changes to a slate with the words, 'LET DOROTHY GO TO THE CITY OF EMERALDS.' The Witch of the North kisses Dorothy for protection and tells Dorothy to walk the yellow brick road to Emerald City to ask the great wizard Oz for help.
Dorothy readies herself for the journey to Emerald City, packing food into a basket and dressing herself in a clean, blue-and-white checked gingham dress and the Silver Shoes of the Wicked Witch of the East. As she walks the yellow brick road, she sees a Scarecrow on a pole in a cornfield. The Scarecrow winks at her and asks Dorothy to free him from the pole. Dorothy frees the Scarecrow, and he decides to travel with her to Oz to ask the Great Wizard for a brain. The Scarecrow reveals the only thing he fears - a lighted match.
Dorothy and the Scarecrow continue down the yellow brick road, which has become uneven and full of holes. The Scarecrow asks Dorothy why she would want to leave beautiful Oz to return to dry, gray Kansas. Dorothy responds that there is no place like home. The Scarecrow tells Dorothy of how a farmer made him and how he was not a good Scarecrow. The crows ignored the Scarecrow and ate the corn. One old crow told the Scarecrow that whether a crow or a person, brains are the only things worth having in this world. Dorothy, Toto, and the Scarecrow continue walking until dark and stay at a little log cottage for the night.
The next day, Dorothy, Toto, and the Scarecrow seek out water. Near the water, they find a man made of tin. The Tin Woodman is so rusted, he cannot move. Dorothy frees the Tin Woodman by oiling his joints. The Tin Woodman decides to join the venture to Emerald City so he can ask Oz for a heart.
The forest grows ominous, tangled with dried branches and leaves. The chitter of birds disappears, replaced with the growls of wild animals. Dorothy, the Scarecrow, and the Tin Woodman hear a terrible roar, and a Lion leaps out of the woods and hits the Tin Woodman and Scarecrow. When the Lion tries to bite Toto, Dorothy slaps the Lion on the nose and calls him a coward. The Lion cries and admits he roars to cover his cowardice. The Lion joins the venture to the Emerald City to ask the great Oz for courage.
The party encounters a great ditch which crosses the yellow brick road and divides the forest as far as they can see. The Lion springs back and forth over the ditch, carrying the others on his back. They reach a deep, dark part of the forest where the Kalidahs live. Kalidahs are horrible beasts with tiger heads, bear bodies, and long claws. They come across a deeper, wider ditch the Lion cannot spring across. The Tin Woodman chops down a tree to make a bridge. As the party crosses the bridge, the Kalidahs chase them across the tree. The Tin Woodman chops the end of the tree, which falls, dashing the Kalidahs to pieces on the sharp rocks at the bottom of the ditch. As they continue on the yellow brick road, they emerge from the dark woods to find a beautiful country of meadows and fruit trees. They must cross a broad river to continue, and the Woodman builds a raft from fruit trees.
The next morning, the party tries rafting across the river, but they are swept downriver toward the lands of the Wicked Witch of the West. The Scarecrow becomes stuck on a pole in the middle of the river, and the others continue to float downriver. The Lion jumps into the water and pulls the raft to shore. The group walks back upriver and rescues the Scarecrow, with the help of a Stork. The group tries to cross a meadow of red poppies, but the odor of the poppies causes Dorothy, Toto, and the Lion to fall asleep. Not made of flesh, the Scarecrow and Tin Woodman are immune to the poppies, and they carry Dorothy and Toto out of the poppy field.
The Scarecrow and Tin Woodman encounter a yellow Wildcat chasing a mouse. The Tin Woodman kills the Wildcat, saving the Queen of all the Field Mice, who has thousands of mice at her command. The Tin Woodman directs the Queen Mouse to send for her mice and ask each to bring a long piece of string. The Woodman cuts down trees and makes a truck on wheels. The Scarecrow and Woodman use the strings to fasten the mice to the truck. The Scarecrow and Woodman load the Lion on the truck and the mice pull the truck out of the poppy field.
The party reaches the land of Oz. The country is beautiful, and the fences and houses they pass are painted green. They stop at a farmhouse, and the woman gives them supper and a place to sleep. The farmer tells them that Oz is a Great Wizard, who can appear in any form he wishes. He also tells them that no one is allowed to see the Wizard's true form. They next day the group arrives at the Emerald City, which is surrounded by a great green wall and has a big gate studded with emeralds. Dorothy rings the bell and the gate opens. They meet a little green man, the Guardian of the Gates, who asks them what they wish for. The Guardian of the Gates asks them to put on green glassed spectacles and says he'll take them to the Palace of the Great Oz. All inhabitants of Oz wear the spectacles and they are locked on. The Guardian says the spectacles prevent blindness from being exposed to the brightness and glory of Emerald City.
Green marble houses and streets studded with sparkling emeralds adorn Emerald City. Even the sky above is tinted green. The people of Emerald City all wear green clothing and have greenish skin. After learning of Dorothy's silver shoes and the mark of the Good Witch, Oz agrees to see Dorothy and the others. The members of the group are admitted one at a time to see Oz. Oz appears as a bodiless head to Dorothy, a lovely lady to the Scarecrow, a terrible beast to the Tin Woodman, and a ball of fire to the Lion. Oz agrees to help them if they kill the Wicked Witch of the West.
When the group enters the Wicked Witch's territory, she summons a pack of huge wolves, a murder of crows, a swarm of bees, and an army of Winkies to kill the group. However, the group defeats all of the Witch's minions. The Witch uses her Golden Cap to summon the Winged Monkeys. The Monkeys seize the Tin Woodman and drop him on sharp rocks. They pull all of the straw out of the Scarecrow. They carry the Lion and Dorothy to the Witch. The Witch imprisons the Lion and forces Dorothy to clean and sweep. When the Witch steals one of Dorothy's silver shoes, Dorothy throws a bucket of water on her. The Witch melts and dies from the water. Dorothy retrieves her shoe and frees the Lion.
Dorothy frees the Lion and the yellow Winkies. Grateful for their freedom, the Winkies fix the Tin Woodsman and the Scarecrow. The group decides to return to Emerald City to claim Oz's promises. Not knowing its power, Dorothy wears the Golden Cap of the Winged Monkeys.
As the group heads east toward Emerald City, they become lost. Dorothy blows her whistle to call the mice for help. The Queen tells Dorothy to use the Golden Cap to summon the Winged Monkeys to carry them to Emerald City. Dorothy uses the Golden Cap, and during the journey, the King Monkey tells her the tale of the Golden Cap.
The group arrives at Emerald City and shares the news of the Wicked Witch's demise. Oz stalls for days, only agreeing to see the travelers after the Scarecrow threatens to sick the Winged Monkeys on him. The all go to the Throne Room, but do not see Oz. Instead, they only hear his voice. They ask Oz to keep his promises, but Oz asks them to return the next day. The Lion roars to frighten the Wizard, causing Toto to jump and tip over a screen in the corner. A little old bald man is revealed in the corner, who reveals he is the true form of Oz. Oz is a common man from Omaha, who went up in a balloon and blew away to this land. Oz reveals that things in Emerald City are not all green, the spectacles just make them look that way. Oz instructs them to return in a day or two, and says he will keep his promises.
The next day, Oz gives the Scarecrow brains of pins, needles, and bran, installs a pretty silk heart into the chest of the Tin Woodman, and feeds some liquid courage to the Lion. Oz is still not sure how to return Dorothy to Kansas.
Four days later, Oz sends for Dorothy. He plans to make a silk balloon and to fly Dorothy over the desert surrounding the lands. Dorothy and Oz sew the balloon, coat the inside with glue, and attach a basket. The people of Oz gather to watch the balloon take off. From the basket, Oz tells the people the Scarecrow is their new leader. The Tin Woodman chops wood for a fire, and hot air fills the balloon and makes it rise. As Dorothy looks for Toto, the balloon breaks free of its restraints and lifts Oz into the sky, leaving Dorothy and Toto behind.
Dorothy uses the Golden Cap for a second time to summon the Winged Monkeys to carry her over the desert. The Monkey King tells her the Winged Monkeys cannot cross the desert. The soldier with the green whiskers suggests Dorothy ask Glinda, Good Witch of the South, for help returning home to Kansas. The Scarecrow, Lion, and Tin Man decide to accompany Dorothy on her quest south to find Glinda.
The group encounters a thick wood on their journey south. A tree picks up the Scarecrow and flings him headfirst through the air. The Scarecrow attempts to traverse the woods again but the tree flings him again. The Tin Woodman tries next and cuts a tree in two before it can seize him. The tree begins to shake and allows the Woodman to pass. Another tree seizes Toto, but the Woodman chops that tree too, and the other trees leave the group alone. When they reach the edge of the woods, the group runs into a high white wall. The Tin Woodman decides to make a ladder so they can climb it.
The Woodman builds a ladder and the group climbs over the white wall. The land on the other side has a smooth white floor scattered with tiny china houses, tiny china people, and tiny china animals. The group traverses the china land, encountering a milkmaid, a joker, and a princess.
The group enters an old forest of large trees. They hear a low rumble and encounter a gathering of hundreds of beasts, including tigers, elephants, bears, wolves, and foxes. The largest tiger bows to the Lion, welcomes him as the King of Beasts, and is happy the Lion has come to fight their enemy, a huge spider-like monster. The spider monster has eaten all of the lions of the forest. The Lion defeats the monster by knocking off its head, and the beasts bow to him. The Lion promises to return and rule over them after Dorothy returns to Kansas.
The group comes to a steep hill covered in large rocks. Hidden among the rocks are hundreds of armless Hammer-Heads. The Hammer-Heads use their extendable necks and flat heads to headbutt people down the hill. Dorothy uses the Golden Cap to summon the Winged Monkeys for the third and final time. The Hammer-Heads try to hit the group as it flies over, but cannot reach them. The group crosses the farming country of the Quadlings and asks a soldier for entry to Good Witch Glinda's castle.
Glinda agrees to tell Dorothy how to return to Kansas in exchange for the Golden Cap. Glinda will use the Golden Cap to return the Scarecrow to Oz, the Tin Woodman to the land of the Winkies, and the Lion to his forest. Glinda tells Dorothy her Silver Shoes have always had the power to return her home. All Dorothy must do is knock her shoes together three times and command the shoes to take her home. Dorothy does and is returned to Kansas. She is in her stocking feet, as the shoes have fallen off and are lost in the desert.