Finn is a thirteen-year-old middle school student and Florida resident who wins an audition to become a Disney Host Interactive (DHI). When he sleeps, his consciousness travels to the Magic Kingdom in the form of a glowing, translucent hologram. Athletic, resourceful, and slightly unsure of himself, Finn quickly steps into a leadership position as he works to gather his fellow teen holograms and protect the theme park from dark forces.

Wayne is an elderly Disney Imagineer who worked directly with Walt Disney during the park's early days. He lives in a hidden apartment above the Magic Kingdom fire station and holds deep knowledge regarding the park's magical properties. Gruff and secretive, Wayne acts as a guide to the teenage hosts but refuses to solve their problems for them, forcing them to figure out Walt's hidden clues on their own.

Amanda is a confident middle school student with a deep tan, freckles, and an observant nature. She quickly inserts herself into Finn's mission, using her mother's employee connections and her own strange intuition to help track down the other DHI teens. She maintains a frustratingly secretive demeanor, frequently dodging questions about her background or her specific motivations for getting involved.

Terrence Maybeck is a tall, outspoken teenager who works at his aunt's ceramics store, Crazy Glaze. As a computer whiz, he takes on the responsibility of investigating and protecting the hidden servers that broadcast the team's holographic forms. He is highly skeptical of the Disney producers and prefers to question authority before following orders.

Maleficent is a dark witch from the Sleeping Beauty story who has been brought into the physical world by the intense belief of park guests. She acts as a powerful enforcer for the Overtakers, a group of villains intending to escape the park and cause real-world chaos. Her presence is always announced by a freezing drop in temperature, and she wields dangerous magic against anyone trying to stop her.

Charlene is an athletic and beautiful DHI host who wants nothing to do with the frightening nighttime battles. She actively resists Finn's attempts to organize the team, wishing she could simply enjoy the paycheck and fame of her daytime holographic job. Eventually, she realizes that ignoring the problem will not keep her safe and steps up to help decode clues.

Willa is an intelligent middle schooler who participates in swimming and archery. She is the most observant member of the DHI team, frequently spotting small visual anomalies and hidden letters on the park rides. Though she is soft-spoken, she demonstrates intense focus when the group investigates the Disney attractions.

Philby is the analytical core of the DHI team. He frequently references historical facts about the park's construction and uses online anagram solvers to decode the letters they find. When the group faces physical danger, Philby remains level-headed, acting as a reliable backup to Finn during their deepest infiltrations into the park.

Jez is a beautiful teenager with pale skin, black hair, and gray eyes. She repeatedly shows up wherever the DHI team gathers, expressing a flirtatious interest in both Finn and Maybeck. Her presence is closely tied to the villains' activities, and she actively assists Maleficent in laying traps for the teenage hosts.

Finn's parents are caring and attentive, providing a stable home life for their son. They become increasingly suspicious as Finn regularly wakes up in dirty daytime clothes and exhibits strange injuries. They ground him to keep him safe, entirely unaware that he leaves the house via holographic projection rather than sneaking out the window.

Jelly is Maybeck's sweet, protective aunt and guardian. She runs a local pottery painting shop and becomes highly defensive when her nephew falls into a strange, unexplainable sleep. She reluctantly allows Finn to help, desperate to see Maybeck recover from what appears to be a medical emergency.

Brad is the Disney producer responsible for recording the five teenagers and converting their motions into the daytime DHI holograms. He initially brushes off Finn's warnings about the Overtakers but changes his tune when he realizes the teens are secretly coordinating with the Imagineer, Wayne.

Dillard is Finn's best friend from school. He thinks Finn has lost his mind regarding the theme park stories, but he remains a loyal companion. He generally views girls as a separate life-form and provides Finn with normal, everyday social interactions away from the high-stakes magical battles.