Buddy

It's Buddy! is a 1990s-style children's television series hosted by the titular Buddy, an anthropomorphic talking unicorn with magical powers. Cast members include child actors Freddy, Wade, Josh, and Oliver; Buddy's co-host Betty Bunny; supporting adult characters Mailman Miles and Nurse Nancy; and sentient objects Mr. Mailbox, Couchy the Couch, Clocky the Clock, Strappy the Backpack, Trashy the Trash Can, and Charlie the Train.

Despite an increasingly angry Buddy coercing him, Josh refuses to participate in a dance party and mysteriously disappears. He is replaced with another child, Hannah, while Buddy assures everyone Josh is traveling to utopian Diamond City. When Freddy finds Josh's bloodstained book in the trash, she consults Nancy, who promises to talk to Buddy. Freddy later witnesses Buddy bludgeoning Nancy to death before fatally punching Clocky off the wall. Freddy and Wade convince Hannah and Oliver to escape to Diamond City inside Charlie, but their attempt fails when Buddy kills Charlie and takes Wade away. As Buddy walks towards Freddy, Wade uses a cleaning spray and a lighter to set him on fire, severely disfiguring him. Buddy then stabs Miles to death as Freddy, Oliver, and Hannah escape with Strappy and Mr. Mailbox, whose mouth has been torn off by Buddy after seeing that he had killed Josh, while Buddy impales Wade with his horn.

Meanwhile in the real world, a woman named Grace hires a psychic investigator who leads Grace, her husband Ben, and their sons Timothy and Derek in a ritual to contact a spirit supposedly haunting their house. The television turns on to an It's Buddy! episode, and Grace becomes convinced she had a third child they cannot remember, but Ben dismisses her. At night, Buddy's hand emerges from the screen and pulls Grace into It's Buddy!, where she takes Nancy's role.

Freddy, Oliver, and Hannah gradually realize they cannot remember their lives before meeting Buddy, though Freddy recalls vague memories of her childhood. The children meet elderly cowboy George and his foul-mouthed marionette Willie, who were on a previous Western-themed version of It's Buddy! and have been hiding from Buddy for many years after he killed another child who jokingly sang a mocking version of the series' closing theme song. The children pass out after eating flower petals, which are secretly psychedelic, and awaken to find that George and Willie have left and stolen Strappy.

Buddy finds and kills George with an axe before drowning Willie. He begins to rip Strappy to lure the children, who arrive on bikes and save him. The children reach Diamond City, only to discover it is a miniature model. Buddy arrives and embraces them, ending the "episode" and resetting It's Buddy! with Mailman Justin and a new child named Tyler, who replace Miles and Wade respectively. When Freddy seeks out Grace for a cut on her arm, Grace recognizes Freddy as her missing daughter. Outside, the children antagonize Buddy by singing a mocking version of the closing theme song, causing Buddy to mutate into a larger, monstrous form, Dark Buddy. He kills Justin, Couchy, and Betty before attacking Freddy. Grace sacrifices herself to allow the remaining children to escape.

After Tyler reverts Buddy to his original form, Buddy snaps his neck and pursues the children down a well, severing portions of his own flesh so he can fit. The children hide in a prop room occupied by an elderly unicorn, but Buddy bursts in, kills Hannah, and swallows Oliver alive. Buddy chases Freddy through the hallway outside until Strappy trips him to fall directly onto Mr. Mailbox's post, critically impaling him. Buddy sarcastically congratulates Freddy for being brave and tries to reset the show by singing the closing theme song, but dies. Freddy finds a gymnasium containing several televisions, each displaying a real-world house with a child watching the show from their screens.

Using the televisions, Freddy bursts through the screen into an empty house, emerging into a living room. As Freddy breaks down in tears upon realizing that Strappy and Mr. Mailbox have turned into lifeless objects, the father of the Spanish-speaking family whose house she landed in approaches and asks who she is.