On a riverbank, Alice’s sister is teaching her a history lesson, but Alice is playing with her cat, Dinah, instead of listening, and begins to daydream about living in a nonsensical world. She then spots a White Rabbit in a waistcoat passing by, exclaiming that he is “late for a very important date”. Alice gives chase, following him into a large, furnished rabbit hole. She falls down into a vertical passage, and sees the Rabbit disappear into a room and leave through a tiny door. She tries to follow him but is too big to fit through the door, whose talking knob advises her to alter her size by drinking from a bottle marked “Drink Me”, which appears on a table. The contents cause her to shrink rapidly. Unfortunately, the door is locked and the key is on the table, out of reach. A box of cookies appears before Alice, and she tries one marked “Eat Me”, and grows so large that her head hits the ceiling. Upset, she weeps large tears which flood the room. She drinks the last of the contents in the bottle and shrinks again, easily floating through the door’s keyhole and into Wonderland inside the bottle. She meets numerous strange characters, including the Dodo, who invites her to take part in a caucus race to get dry, and Tweedledum and Tweedledee, who recount the tale of “The Walrus and the Carpenter”.
Alice tracks the White Rabbit to his house; he sends her to retrieve his gloves after mistaking her for his housemaid. While searching for them, she eats another cookie marked “Eat Me” from the Rabbit’s cookie canister and grows large again, getting stuck in the house. The Rabbit, thinking Alice is a monster, brings the Dodo to his house to help him get rid of her. After chimney sweep Bill the Lizard fails to remove her from the house after she sneezes him out, they plot to burn the house down, but Alice escapes by eating a carrot from the Rabbit’s garden and shrinking to the size of an insect. She meets a garden of talking flowers who initially welcome her with a song, but then mistake her for a weed and order her to leave. Alice then encounters a Caterpillar, who becomes enraged after she tells him she is distressed at being three inches tall, as he is the same height, and turns into a butterfly. Before leaving, he advises her to eat a piece of his mushroom to alter her size. She does so, and after a few mishaps in which she grows large again and shrinks back to three inches tall, she manages to return to her original size. Alice keeps the remaining pieces of the mushroom on hand, and continues to pursue the White Rabbit.
In the woods, Alice meets the Cheshire Cat, who advises her to visit the Mad Hatter or the March Hare to find out where the White Rabbit is. She chooses to visit the latter, but finds both, along with the Dormouse, at his house having a mad tea party and celebrating their “unbirthday”. When she arrives at the party, they celebrate her unbirthday too, but Alice becomes frustrated at them interrupting her every time she tries to speak or drink tea. The White Rabbit appears, continuing to exclaim that he is late; the Hatter examines his pocket watch and says it is “two days slow”, and attempts to fix it by filling it with food and tea but ends up having to destroy it after it goes “mad”. The Rabbit laments that his watch was an “unbirthday present”, and the Hatter and Hare sing “The Unbirthday Song” to him before throwing him back into the woods. Fed up with the nonsense surrounding her, Alice leaves and decides to abandon her pursuit of the Rabbit and go home. She goes back in the direction she came from, but her surroundings have completely changed, and she is lost in the Tulgey Wood. Fearing she is lost forever, Alice sits on a rock sobbing.
The Cheshire Cat reappears and advises Alice to ask the Queen of Hearts for directions home, showing her a “shortcut” into a giant hedge maze ruled by the tyrannical Queen and her meek husband, the King. The Queen orders the beheading of anyone who enrages her, including a trio of playing card gardeners who mistakenly planted white roses instead of red ones. Alice is invited (or rather forced) to play against the Queen in a bizarre croquet match; live flamingos, card guards and hedgehogs are used as the equipment. The animals and card guards rig the game in favor of the Queen. During the game, The Cheshire Cat appears again and plays a trick on the Queen, causing her to fall over. She blames Alice for this, and the girl is arrested and put on trial.
At Alice’s trial, the Mad Hatter, March Hare and Dormouse are called to the stand as witnesses, briefly celebrating the Queen’s unbirthday and giving her a headpiece as a present, which turns into the Cheshire Cat. Chaos ensues when the frightened Dormouse runs around the courtroom after Alice points this out, and the Queen’s crown is accidentally ruined after being hit by a mallet. Again, she blames Alice. Alice remembers that she still has the pieces of the Caterpillar’s mushroom and quickly eats both, growing large once again. The King and Queen order her to leave the courthouse, but she refuses, calling the Queen “a fat, pompous, bad-tempered old tyrant”. As she rebukes the Queen, she returns to her normal size. Enraged, the Queen orders her execution. Alice flees, and the Queen, King, card guards and other characters give chase. As she flees, she re-encounters some of the other characters she met earlier, some of whom join in chasing her. Alice reaches the small door she encountered at the beginning of the film. The doorknob informs her and shows her that she is actually outside, asleep with Dinah. As the mob approaches her, she shouts for herself to wake up. She wakes up. She, her sister, and Dinah leave the riverbank to go home as the film closes.