On Christmas Eve, Clara Stahlbaum (Mackenzie Foy) shares her latest invention—a complex device designed to catch mice—with her brother Fritz (Tom Sweet). Afterwards, they join their sister Louise (Ellie Bamber) and their father, Mr. Stahlbaum (Matthew Macfadyen), as he carefully decorates their Christmas tree. Fritz remarks that the ornamentation isn’t quite the same as their mother Marie (Anna Madeley) used to do, which visibly affects everyone present. That evening, Mr. Stahlbaum gifts his children early presents from their late mother, including a mysterious porcelain egg that requires a key to open. Clara is disappointed when she finds no key, but she discovers a note from Marie telling her that everything she needs is inside.
The family then attends a festive party hosted by their godfather Drosselmeyer (Morgan Freeman), who was a guardian to Marie when she was an orphan and witnessed her rise as an ingenious inventor. When Mr. Stahlbaum requests his daughters stay to dance, Clara seizes a moment to find Drosselmeyer instead. She brings him the locked egg, and he recognizes it as an item he once crafted for Marie but admits he doesn’t possess the key either. Drosselmeyer then creates a setup using strings to help the children locate their gifts, but when the others are busy, Clara wanders off, guided by a string that takes her through a mysterious hall leading to another world.
In this strange new realm, Clara spots the elusive key but is quickly chased by Mouserinks, a tiny rodent. The chase takes her onto an icy lake, where she encounters Captain Phillip Hoffman, known as the Nutcracker (Jayden Fowora-Knight). When Clara introduces herself and mentions her mother, Phillip unexpectedly addresses her as “Your Majesty,” displaying a regal demeanor, and helps her pursue Mouserinks. Together, they ride his horse into the enchanted forest of what is called the Fourth Realm—a world inhabited by mice and ruled by a fearsome mouse leader, Mother Ginger (Helen Mirren). She rises amid the chaos and calls for Clara, but Phillip swiftly rescues her.
Their adventure leads them to a grand castle where they meet the leaders of the other realms—the regents—including Hawthorne (Eugenio Derbez), ruler of the Land of Flowers; Shivers (Richard E. Grant), of the Land of Snowflakes; and the Sugar Plum Fairy (Keira Knightley), guardian of the Land of Sweets. There, Clara learns from the regents that Marie has tragically passed away. The land is called the Land of Amusements, but the name has been rejected by the inhabitants due to the corrupt influence of Mother Ginger.
As Clara explores the vibrant world, she experiences a ballet performed by a Ballerina (Misty Copeland) that tells the story of how their universe came into being at Marie’s arrival. She also sees her mother’s beloved invention, which is unlocked via the same key that opens the porcelain egg. Later that night, Clara dreams of her mother and the toys she cherished, including a nutcracker that resembles Phillip.
The next day, driven by Sugar Plum’s encouragement, Clara leads an army—alongside Phillip—to retrieve the key from Mouserinks. They venture into the Fourth Realm where armies of mice and creepy clown-like creatures, who resemble nesting dolls, threaten. Clara confronts Mother Ginger herself, who is upset about Marie’s death, but Phillip courageously intervenes. Eventually, they succeed in retrieving the key from Mouserinks, but Clara finds that the egg is merely a plain music box once opened, failing to reveal any hidden secrets.
Back at the castle, Clara hands the key to Sugar Plum, who uses it to activate a machine. This device transforms toy soldiers into larger, living warriors. However, her true motive is revealed: Sugar Plum intends to take over all the realms in retaliation for Marie’s absence and devotes her efforts to power, framing Mother Ginger. Her plan involves turning the land into her domain by manipulating her army, and she begins to threaten the peace of the entire universe.
Clara and her allies—along with the captured Mother Ginger—face imminent danger as Sugar Plum initiates her destructive plans. Clara, realizing her inner strength and the message from her mother that "everything you need is inside," works to outsmart Sugar Plum. She discovers that she can turn the machine against her, and with Phillip’s help, she manages to turn Sugar Plum into a doll, breaking her control over the toy soldiers and restoring balance.
With peace restored, the territories of the Fourth Realm, Land of Flowers, and others are freed from Sugar Plum’s tyranny. Hawthorne and Shivers are released from their chains, and Mother Ginger resumes her role as the regent of the Land of Amusements. Phillip is appointed captain of the guards, with Mouserinks now a loyal sidekick. Clara is celebrated for her bravery, but she soon realizes she must return home. She bids farewell to her new friends, and they watch her leave with a sense of hope for the future.
When Clara returns to the party, she finds Drosselmeyer, who recognizes that Marie’s favorite invention was ultimately Clara herself. Inspired, she approaches her father Mr. Stahlbaum outside, and they share a heartfelt apology—Clara for missing the dance, and her father for his earlier remarks. They begin to dance together, opening Marie’s cherished music box, which fills the air with the first song they ever danced to. Her siblings, Louise and Fritz, join them, completing a moment of reconnection and celebration.
This magical story underscores themes of family, inner strength, and the idea that sometimes, everything we need is already inside us, waiting to be discovered.
