This prequel to The Wizard of Oz begins in Kansas in 1905 (presented in black-and-white with a standard frame), where we meet Oscar Diggs (played by James Franco), an ambitious illusionist and con man who works for a midwestern traveling circus. Despite his lofty ambitions, Oscar's career is stalling; his tricks are more illusion than reality, his attire is ragged, and he barely scrapes by financially. His assistant, Frank (voiced by Zach Braff), bursts into Oscar's caravan just as he is attempting to impress a new assistant, May (Abigail Spencer), by giving her a small wooden music box—an heirloom he claims to have inherited.
Frank reminds Oscar that it's almost time for their next performance. He hands Oscar a hat filled with coins, from which Oscar hesitantly takes some for himself, much to Frank's annoyance. As the show commences, a young girl in a wheelchair (Joey King) becomes captivated by Oscar's act. Amidst the chaos, however, Oscar's grand illusions come crashing down when a heckler reveals the visible wires suspending May during a levitation trick. Following a chaotic finale, where Oscar ultimately reveals May’s absence, he is confronted by the little girl's desperate plea: “Make me walk!” Unprepared for the challenge, Oscar deflects, saying, “I’m not that kind of wizard, kid.” The audience quickly turns hostile.
Outside the tent, a storm brews as chaos unfolds around the circus. Frank tells Oscar about a female visitor in his caravan. Enter Annie (played by Michelle Williams), an old flame. Their chemistry is palpable, but Oscar's reputation as a womanizer regrets their missed connection. Meanwhile, May learns about Oscar's duplicity, igniting feelings of betrayal. An impending tragedy surfaces when a furious strongman—who happens to be Annie's suitor—chases Oscar all over the fairground. In a scramble, Oscar hops into a hot air balloon to escape, only to find himself caught in a massive tornado that launches him into the vibrant and mystical world of Oz.
Upon landing, Oscar is bewildered to discover sentient plants and small mischievous fairies as he calls for aid. Here, he meets Theodora (played by Mila Kunis), a captivating young witch who reveals to him a prophetic destiny: a wizard named Oz is foretold to arrive and save their land from the Wicked Witch. Taken by Theodora's charm, Oscar introduces himself and makes light of witches, only to be reminded by Theodora that she is indeed a good witch. As danger lurks in the form of a winged minion, Oscar employs a quick-thinking ruse with a dove and escapes with Theodora.
Their path brings them to the Emerald City, where Theodora confesses her growing affection for Oscar. Eager to win her over, he gifts her a wooden music box, a sentimental token he’s offered many women before. Their adventure continues with another encounter where they rescue Finley, a winged Capuchin monkey (voiced by Zach Braff), caught in a tangle of man-eating plants, thus solidifying their camaraderie. Despite all of this, Oscar remains uncertain about his abilities, acknowledging he is merely a con artist, not the powerful wizard they believe him to be.
The trio sets off deeper into Oz, coming across a haunted porcelain town where they meet a young girl, the China Girl (voiced by Joey King), who has been damaged by the Wicked Witch's rampage. Oscar trades glue for loyalty and they continue towards an ominous cemetery, where the disguised Wicked Witch waits. Their journey of peril reveals an intricate web of deception when the witch—now unveiled as Glinda (raspberry pink clad, the same actress as Annie)—informs them of her sister, Evanora (played by Rachel Weisz), and her nefarious plans for power.
As the Wicked Witch's forces close in, the group must summon their courage and craft illusions to save themselves from imminent danger. Oscar's bravado leads to a series of attempts to outsmart the witches, culminating in his ultimate confrontation with Evanora, who has turned Theodora into a bitter and twisted version of herself. This metamorphosis forces Oscar to confront not only his identity but the very nature of good and evil in Oz.
In a final showdown filled with visual spectacle—a flying balloon, mechanical illusions, and cascading fireworks—Oscar’s true journey is revealed. The villagers unite against their oppressors, resulting in a climactic duel between Glinda and the Wicked Witch. Ultimately, Oscar embraces his role, not as a real wizard but as a symbol of hope and courage for those around him. The morning after all has transpired, Oz, now recognized for his true essence, rewards his friends and allies—showcasing gifts of gratitude, as he can finally weave his magic not through trickery but through genuine friendship and bravery. He shares a heartfelt moment with Glinda, sealing their bond with a kiss.
