Minna, Emilie Kroyer Koppel, is a young girl who lives in the rural countryside with her father John / Milo, Rasmus Botoft, after her mother Karen Mitchles, Alberte Winding, left to pursue a singing career. Minna struggles to adjust to the arrival of John's new wife, Helene, Ditte Hansen, and her daughter Jenny, Caroline Vedel Larsen, who regularly quarrel with Minna. The family dynamic is tense at first, but Minna clings to a sense of home even as the house fills with new faces and rivalries.
One night, Minna dreams of a hole in the sky and blue creatures that seem to control her dream, who abruptly wake her. The next night, she investigates and discovers that these blue figures are Dreambuilders, designers of people’s dreams, and she meets Gaff, Martin Buch, a Dreambuilder who guides her through this hidden world. While hiding from the Inspector, Stig Hoffmeyer, Minna is knocked off her dream stage and into her father’s dream, accidentally altering it when she hands him a can of anchovies instead of the cake that was scripted. The moment she wakes, she realizes the power she now wields: by touching a dream, she can influence real-world feelings and choices.
In waking life, the unintended dream tampering has a surprising effect: John now loves anchovies, a change that reveals how easily dreams can shape behavior. Minna begins to see how she might influence people—carefully, one dream at a time. She turns her attention to Jenny, who threatens to take Minna’s hamster Viggo to the animal shelter. Desperate to protect her pet and her place in the family, Minna pleads with Gaff to help sway Jenny, and the two sneak into Jenny’s dream to plant new, protective imagery: a mechanical, giant-sized Viggo. The plan relies on Milo’s help, a former Dreambuilder who was demoted to janitor after an earlier mishap, and his experience becomes crucial as Minna navigates the dream world and its dangers. In the dream realm, Minna learns a chilling rule: if a dreamer stays out of their dream stage for too long, they cease to exist.
Back in the real world, Jenny’s mood shifts as she notices the changes in her sister and friends. Jenny’s behavior becomes increasingly erratic—Minna’s fashion sense and the sweater she loves become a source of tension, amplified by social media scrutiny. Minna attempts to fix things with Jenny by coaxing her to like the sweater, but she almost gets caught by the Inspector during a close chase through the dreamscape. Jenny starts to bond with John, which sparks jealousy in Minna and sets the stage for a dangerous plan. In a moment of reckoning, Minna creates a nightmare for Jenny that exploits Jenny’s arachnophobia with a terrifying, mechanical spider. The nightmare spirals out of control, and the dream stage collapses; Jenny slides into the Dream Trash, a discarded set of dream stages where old dreams are retired, and Minna’s heart sinks as reality bleeds into fantasy. The Inspector blames Gaff for the catastrophe and demotes him to janitor, while Jenny remains in a coma in the real world. Guilt-ridden, Minna reconciles with John and vows to save Jenny.
In the dream world, Minna encounters her mother, who appears as a caregiver trying to keep her in bed, only to reveal that she is an actor behind the scene. With Gaff’s help, Minna evades the Inspector again and enters the Dream Trash to rescue Jenny. Their escape route is blocked when the tower that leads out of the Dream Trash is destroyed, leaving them stranded among ruined dream sets. They hide in the remnants of one of Jenny’s former dreams and uncover a painful truth: Jenny’s father left her and Helene years ago, a wound that explains some of the friction in their family. Reaching for hope, the two sisters discover an old dream controller and use it to levitate large objects, building a makeshift ladder to reach a functioning dream stage. They are pursued by the spider, but with assistance from Gaff, Minna manages to deactivate it. Jenny begins to fade from the dream stage again, but Minna, Gaff, and the Inspector work together to return her to her stage and wake her just in time.
Back in the real world, Jenny awakens from her coma, and the family—Minna, Jenny, John, and Helene—find a way to come together once more. In the dream world, Gaff is reinstated as a Dreambuilder and begins construction on a new dream, signaling a fresh start and a future where dreams can be used to heal rather than harm. The movie closes on a note of renewed family connection and a cautious optimism about the power of dreams to shape reality for the better.
