Cinderella (Camila Cabello) is an ambitious young woman who wants to establish her shop "Dresses by Ella". She lives with her cruel step mother Vivian and her 2 daughters, who treat her like a servant of the house. RObert has just refused the hand of Princess Laura (Mary Higgins), the daughter of Lord Reginald. This marriage would have given King Rowan control of far reaching territories and he is furious at RObert for refusing the proposal. Rowan threatens Robert that if he doesn't fall in line, he will give the crown and the Kingdom to Robert's sister Gwen. Rowan organizes a ball and invites all pretty ladies of the state to it, so Robert can chose his future wife.Rowan discourages Gwen from participating in the affairs of the state (as he is traditional in the sense of the eldest son taking over the throne), and gives a long rope to Robert to find a suitable mate, and fulfill the condition of becoming a King.One day in her patriarchal society, Cinderella catches the eye of Prince Robert (Nicholas Galitzine) in the guard-changing ceremony. The next day, Robert, dressed as a commoner, goes to the market, where he finds Ella trying to sell her dress. After some playful banter (she laments that women aren't allowed to own a business in the Kingdom), he buys it for three times the amount she originally asked. He later invites her to the ball being held two weeks later, with the promise of introducing her to various people from the world to sell her dresses to.When the day arrives, Ella is getting ready when her stepmother, Vivian (Idina Menzel) throws ink on her dress and tells her that only her stepsisters, Malvolia (Maddie Baillio) and Narissa (Charlotte Spencer), can attend, since Thomas (Rob Beckett) the vegetable merchant has already confirmed his desire for Ella's hand. Ella is sad, but her Fabulous Godmother (Billy Porter) magically appears and dresses her in a design of Ella's, with glass shoes, and turns mice (Rob the Mouse (James Corden), Simon the Mouse (James Acaster) & Frankie the Mouse (Romesh Ranganathan)) into footmen and a crate into a carriage.Ella goes to the ball and meets Tantiana (Beverley Knight), a visiting queen who offers to take her around the world as a dressmaker for her and asks to meet her the next day in the market square. Later, Robert finds Ella, shows his sister, Princess Gwen (Tallulah Greive) wearing the gown he bought from Ella previously and proposes to Ella. Ella refuses, however, as she wants to start her career. She tells that if she marries him it will be the end of her dream and Robert from his small age wanted to become the king and he also is not ready to accept this. At the stroke of midnight, she leaves the hall after throwing her shoe at one of the King's attendants, who tries to catch her.The next day, Vivian, tells Ella her life story that she was also an ambitious girl like Ella and even had got an opportunity to learn piano in a reputed music school. She left home to study and when she came back home her husband gave her divorce saying that she is not a suitable wife and kicked her and her daughters out. While she was about leave Ella's room she finds Ella's glass slipper and, on knowing the truth that her stepdaughter is the mystery princess, tries to convince Ella to marry Robert. When Ella refuses, Vivian gives her to Thomas.Meanwhile Rowan is furious with Robert and says he doesn't care if Robert loves Laura or not and orders his marriage to her by the end of the week. Robert laments to Rowan that Cinderella didn't return his love. When the king entered into the queens's room she does not take any notice of him. To which the queen replies that this is family and love is important. The king says that he loves Robert and she says that he loved him before he became a king and that he is not paying any respect to her and not even accepting her words. She even tells since he became the king he only thought of expanding his kingdom. Robert's mother, Queen Beatrice (Minnie Driver), helps his father, King Rowan (Pierce Brosnan), understand that it will be right to let him marry a commoner. The king thinks of these words and allows the prince to marry his love. Rowan even gives him the glass slipper. Robert keeps searching for Ella and finds her running in the forest after she escapes from Thomas. They confess their love to each other as Ella and Robert kiss and reach the market in time to show her benefactor her designs, who accepts them and asks Ella to travel with her.Robert introduces Ella to Rowan and Beatrice and informs them of their decision to travel the world. He knows this will ruin the plan for his future ascension to the throne, but Beatrice smiles as Rowan proudly declares that Gwen (who has repeatedly shown an interest and ability in affairs of state), will now be first in line to the throne. Citizens of the kingdom gather to witness the ceremony announcing the Princess' position and that Robert and Ella are in love.