Elvira and Alma are two sisters navigating the complex dynamics of family and societal expectations after their mother, Rebekka, marries an older man in pursuit of wealth and status. This union brings them into the life of Agnes, the daughter from her new husband’s previous marriage. Shortly following the wedding night, tragedy strikes as Agnes' father passes away, leaving the family in a precarious financial situation, revealing that he was actually broke.
In a desperate bid to secure a prosperous future, Rebekka decides it would be best to marry off one of her daughters, settling on Elvira since Alma is still too young. Although Elvira harbors fantasies of winning the affections of the charming Prince Julian, Rebekka is acutely aware of the societal view that her daughter may not meet the conventional standards of beauty. As stress builds around the looming competition for Julian’s attention from Agnes, who is perceived as more attractive, Rebekka embarks on a drastic plan to enhance Elvira's desirability.
In a series of agonizing procedures, Elvira undergoes surgeries and artificially manipulates her body by swallowing a tapeworm to attain her ideal weight. This journey becomes profoundly isolating as Elvira’s admiration for Agnes warps into bitter resentment, fueled by her belief that Agnes possesses talents and beauty without any effort. Everything comes to a head when Elvira discovers Agnes in an intimate encounter with Isak, a stableman. In a fit of anger, she informs Rebekka, who swiftly punishes Agnes by demoting her to a servant, turning her into a modern-day Cinderella.
As the royal ball approaches, Elvira's health declines because of her drastic measures to fit the image of a princess, resulting in hair loss and malnutrition. The tension escalates when Rebekka’s relentless pursuit of beauty for Elvira pushes her daughter into uncomfortable situations, such as an inappropriate advance from a dress seller, further igniting the animosity between the sisters. A chaotic night follows as Alma experiences her first period alone, while Agnes is haunted by memories of her father, receiving ghostly warnings from her mother about the ball’s timing.
When the ball finally arrives, Elvira captures the attention of Prince Julian, but his gaze soon shifts to the mysterious Agnes. Devastated, Elvira finds herself regurgitating the consequences of her unhealthy choices. As the evening unfolds, both sisters return home, leading to a shocking twist where Elvira tries to secure her chance by commandeering Agnes’ lost slipper, revealing her desperate and twisted determination as she resorts to cutting off her toes to fit into it.
In a moment of horror, Elvira’s method is interrupted by Rebekka, who coldly sedates her. The following day, as Elvira is on the brink of despair, she realizes her efforts have been in vain as Agnes finds true love with the prince. In a moment of clarity brought on by her sister’s plea, Elvira takes an antidote and expels the tapeworm, symbolizing her decision to break free from their mother’s oppressive grip. Ultimately, the sisters join forces to reclaim their lives away from Rebekka’s suffocating expectations, signifying a new beginning as Rebekka, oblivious to their rebellion, pursues newfound romantic interests from the ball.
