When Mickey falls asleep reading Lewis Carroll's Alice Through the Looking Glass, he dreams he travels through his own mirror into a backward version of his house. After meeting some of its strange inhabitants, he eats a walnut that was thrown at him by a pair of pliers. The nut ends up rapidly growing him to the size of the house, and then rapidly shrinks him down to a size perfect for dancing with a telephone, a pair of gloves, and a deck of playing cards. However, when the King of Hearts sees Mickey dancing with his Queen, he becomes jealous and sends the cards after him. After an exciting chase, Mickey escapes back through the mirror and wakes up in the safety of his normal house.
Mickey falls asleep after reading Through the Looking-Glass by Lewis Carroll. An astral projection of himself (presumably Mickey in his dream state) leaves his body and passes through his mirror into an alternate version of his house. His furniture and possessions have come to life and are complete with faces and personalities, but most of them remain motionless. He jumps on a rocking chair that throws him off in annoyance while a nearby coat rack watches in surprise, and lands on the footrest that behaves like a puppy while Mickey rides on it like a horse until it jumps into the rocking chair. While the chair tries to calm down the footrest, Mickey tries to comfort them, only to end up angering them instead. He bumps into an umbrella, who scolds him until it suddenly drops open and recloses itself in embarrassment before returning to where it originally was. Mickey then comes across a nut cracker breaking open a walnut, who then offers it to him while it eats the shells. After eating the walnut, Mickey's belly commences to wildly spin around, and it hits his face. While his belly crazily spins, he suddenly becomes gigantic and then shrinks. The telephone suddenly rings and it throws its receiver down to Mickey, who uses it to climb up to the table. He attempts to answer the call, only to get responses from the phone itself and then proceeds to jump rope with the telephone, who uses its receiver and wire as a jump rope while the radio begins playing music. Mickey begins to dance his way through his house, tap dancing on a top hat (wearing a tiny one with a match for a cane) with some gloves (eventually he gets his butt kicked twice by the gloves), playing cards (some of them hit Mickey's butt during the dance), and eventually the Queen of Hearts card (who resembles Greta Garbo). The joker on his bicycle notices and alerts the King of Hearts who uses the joker's bike to get down there and pulls the queen aside before proceeding to fight for his lady in a sword duel with Mickey, who uses both a sewing needle and a button as a makeshift sword after the King of Hearts pushes him and gets his butt stabbed by the needle. Mickey defeats the king by pushing him into an inkwell, where a stamp takes him out and cleans him. Considering this as the last straw, the king then orders for the cards to be called out to get rid of Mickey for good and the radio acts as an alarm to summon the cards like police cars - "Calling all cards! Calling all cards!". In response, an army of cards come out from the king's throne and at the same time, a nearby drawer opens as more cards emerge from it. Chaos ensues as Mickey runs from the cards, bumping into a stack of books along the way. He picks up a fountain pen, hides in a basket of yarn, and uses the pen like a machine gun to fire ink at the cards while wearing a thimble like a helmet. The pen eventually runs out of ink, allowing the cards to pig-pile on Mickey, who then escapes in a torn sock. After being spotted, the cards give chase again and throw their pictures at him. Mickey then turns on an electric fan to blow the cards back while the telephone calls the police in panic as Mickey swings from a lamp rope and runs on a globe until he trips and falls into the globe's Bay of Bengal and is thrown out by a figure, who appears to be a small version of Neptune, by impaling Mickey's butt. He then grows back to his normal size and escapes back to the real world through the mirror where he reenters his body. Eventually, he is awakened by his alarm clock and it has all been a dream and goes back to sleep after throwing his alarm clock into a drawer.
- Mickey Mouse (voiced by Walt Disney)
- Clothes Hanger
- Umbrella (voiced by Walt Disney)
- Nutcracker Tool (voiced by Clarence Nash)
- Telephone (voiced by Bill Thompson)
- Radio (voiced by Pinto Colvig (hiccup); voiced by Billy Bletcher (Voice)
- Glove #1
- Glove #2
- Joker Card
- King Card (voiced by James MacDonald)
- Queen Card
- King Neptune (cameo)
- The King of Hearts is a caricature of Charles Laughton’s Academy Award-Winning portrayal of King Henry VIII in the 1933 film The Private Life of Henry VIII.
- The Queen of Hearts is a caricature of famous movie actress Greta Garbo.
- When Mickey first steps into the Mirror World, a footstool that acts like a dog can be seen. Said footstool may have been the inspiration for Sultan that appeared in Beauty and the Beast.
- There is a tribute to this film in the "Friend Like Me" scene of Aladdin, where Genie briefly dances with two oversized Genie hands in a similar manner to the way Mickey dances with the gloves in this cartoon.
- The exact scene with Mickey dancing with the gloves also appeared during the Aladdin part of the bubble montage from the Florida version of Fantasmic!
- This short would become the basis of the plot for the GameCube video game Disney's Magical Mirror Starring Mickey Mouse. At certain points, the game's cinematics (including the opening cutscene) replicate animation seen in the cartoon.
- The opening scene of this short was replicated again in the opening cinematic of Epic Mickey. This short is also a transitional level in the game.
- The short was added as a bonus feature on all of the DVD releases of Alice in Wonderland since 2000.
- The music playing when Mickey is dancing with his two oversized gloves was used as background music at the end of tapes in the Walt Disney Mini Classics series, listing all of the other titles in the series.
- The scene where Mickey dances with his hands in his pockets was reused in the Disney Channel closing logo around 1997 to 2002.
- Disneyland, episode #3.8: "The Plausible Impossible"
- The Mouse Factory, episode #2.10: "Mickey Mouse"
- Good Morning, Mickey, episode #4
- Donald Duck Presents, episode #8
- Mickey's Mouse Tracks, episode #52
- Donald's Quack Attack, episode #1
- The Ink and Paint Club, episode #1.50: "Storyteller Mickey"
- Have a Laugh!, episode #24
- Treasures from the Disney Vault, June 28, 2016
- Mickey Mouse and Donald Duck Cartoon Collections, Volume One
- Mickey's Magical World (edited)
- The Spirit of Mickey
- Everybody Loves Mickey
- Walt Disney Treasures: Mickey Mouse in Living Color
- Alice in Wonderland: The Masterpiece Edition
- Walt Disney Animation Collection: Classic Short Films, Vol. 1: Mickey and the Beanstalk
- Alice in Wonderland: Special Un-Anniversary Edition
- Everybody Loves Mickey
- Alice in Wonderland: 60th Anniversary Edition
- Celebrating Mickey
- Disney+, November 12, 2019
Have a Laugh! changes
The following scenes were deleted from the short release due to time constraints:
- The armchair stroking the dog-like footstool and the latter barking at Mickey as he reaches out to touch it.
- Mickey's run-in with a grumpy umbrella.
- Mickey shrinking from the nut is heavily edited, cutting out him growing to giant size before shrinking abruptly.
- All scenes with Mickey's argument with the phone, his entire Astaire-like dance first on the top hat and then with a pair of gloves, and his march with the cards are cut; it shows the radio starting to play the lively number and then cuts to Mickey dancing with the Queen of Hearts card.
- Mickey's duel with the King of Hearts card is cut completely, as well as the latter calling his army of cards; it cuts from the King drawing his swords to the radio "calling all cards".
- Mickey's run from the cards is partially edited: his colliding with a book, his trying to fend them off with a fountain pen, and his trying to hide from them in a sock are all cut.
- The sentient phone calling the police.
- Mickey running across the globe is partially edited, and his falling in its waters and subsequent ejection by King Neptune are cut.