In the waning twilight of her life, the mysterious Grande Dame gathers the Brothers Grimm for a solemn meeting, chastising them for their overly sanitized version of Cinderella. In a demonstration of her discontent, she reveals a beautiful glass slipper and launches into a heartfelt narrative that uncovers the true story of the beloved heroine.
Set against the lush backdrop of the French Renaissance, a decade after the death of Auguste de Barbarac, his daughter Danielle finds herself cruelly treated as a servant by her wicked stepmother, Rodmilla de Ghent, and her conniving stepsisters, Marguerite and Jacqueline. One fateful morning, Danielle's life intersects with that of Prince Henry, who is eager to escape an unwanted engagement to Princess Gabriella of Spain. Mistaken for a thief, Danielle shares a precious moment with Henry, who gifts her coins to ensure their encounter remains a secret from the vigilant Royal Guard.
Soon after, Henry is captured, leading him to a serendipitous meeting with Leonardo da Vinci, who has been invited to the French court by King Francis. Meanwhile, Danielle decides to venture into the palace, disguised as a noblewoman, to rescue Maurice, a devoted family servant sold into servitude by Rodmilla. With Henry's timely assistance, Maurice is liberated, and he finds himself captivated by Danielle's fierce intellect and spirited nature.
As the evening unfolds, King Francis announces a masquerade ball, where Henry must publicly declare his love for his chosen bride at midnight to avoid his impending marriage to Gabriella. Rodmilla, seeing an opportunity to further her own ambitions, schemes to promote Marguerite, her favored daughter. Meanwhile, Danielle grows more enamored with Henry, and their secret meetings fuel whispers among the court.
Their romantic journey takes a perilous turn when they encounter gypsies in a library run by the Francian monks. However, these wandering souls prove to be allies, providing refuge to the star-crossed lovers beneath a starlit sky, where they share their first tender kiss.
As Rodmilla and Marguerite’s plots intensify, they scheme to steal Nicole's cherished wedding gown and glass slippers for Marguerite's debut at the ball. A cycle of vengeance ensues when Danielle retaliates against Marguerite, who then desecrates the precious book Utopia, gifted to her by Auguste. This turmoil culminates in Rodmilla's cruel punishment of Danielle, prompting Jacqueline to show unexpected sympathy, lamenting Marguerite's viciousness.
During a luncheon hosted by Queen Marie, the queen expresses her curiosity about the captivating young woman who has stolen Henry's heart. Rodmilla’s gaze reveals her recognition of Danielle as Nicole's daughter, leading to the shocking revelation that Danielle is already betrothed. As tensions mount, Danielle's secret remains hidden, even as Henry commends her for inspiring him to envision a prestigious institution. Ultimately, the burdens of deception weigh heavily on her heart. When Rodmilla confronts Danielle about her lies and demands the return of the treasured dress and slippers, Danielle bravely stands her ground. Unbeknownst to Rodmilla, the loyal servants have secreted away the items, leaving her in the dark. In a furious response, Rodmilla confines Danielle to a cramped pantry, snuffing out any hope of escape.
Caught in the midst of these schemes, Maurice devises a plan with Gustave to enlist Leonardo's help in rescuing Danielle from her oppressive circumstances. Together, Leonardo, along with Paulette and Louise, prepares Danielle for a daring escape, disguising her in Nicole's finery. With newfound resolve, Danielle seeks to confront Henry and unveil the truth; however, Rodmilla intervenes at the critical moment, exposing Danielle's betrayal to a shocked Henry. His trust shattered, he coldly rejects her.
Devastated, Danielle flees, leaving behind a heart-wrenching memento of their turbulent relationship—a discarded slipper. Subsequently, Leonardo chastises Henry for his mistreatment of Danielle, leaving the slipper at his doorstep as a stark reminder of his error.
In the wake of this turmoil, Henry begins to understand that Gabriella suffers greatly herself, yearning for another. He ultimately decides to cancel their wedding plans. Maurice and Jacqueline deliver shocking news: Rodmilla has sold Danielle into servitude under Pierre Le Pieu. Urgency floods Henry as he races to rescue his beloved, only to learn she has already escaped.
Henry returns, filled with remorse and a professions of love for Danielle, culminating in a heartfelt proposal. As the fitting of the slipper onto her foot symbolizes their renewed connection, Danielle joyfully accepts, sealing their fate together.
With Rodmilla's treachery laid bare, she is summoned before the royal court to answer for her misdeeds. Marie’s trusted advisor strips Rodmilla of her title, threatening her with exile alongside Marguerite unless a champion is found to defend her. In a surprising show of character, Danielle appears in court—not to defend Rodmilla, but to request that the same "courtesy" be shown to her that Rodmilla had once denied her.
Finally, justice is served as Rodmilla and Marguerite descend to the status of mere servants, laboring in the palace laundry. In a kind gesture, Leonardo gifts Danielle and Henry with a treasured portrait of their beloved, a masterpiece that would find its place on the walls of the esteemed university, enduring long enough to witness the upheaval of the French Revolution.
