Pixie's Secret Agency is a top-secret agent force located in Club Penguin, a humanlike settlement on a large island made of ice. An uneventful day at the PSA HQ is interrupted when Agent Hailey, an anime neko goes missing. After a brief inspection of the HQ, Agent Pixie (the director of the PSA) finds a green transparent note that reads "On the 13th floor. Don't keep me waiting."
The penguins realize that the note is referring to the 13th floor of the Puffle Hotel, a puffle-themed hotel located in Club Penguin's central plaza. Pixie and agents Charlie and Poko go to investigate. There they meet Charlie's childhood friend Skip, who is now a bellhop working on the hotel. Skip lives on the private 13th floor and agrees to let them onto it. There they discover a strange green mist surrounding it that resembles the ectoplasmic material the ransom note was made out of.
The source of the green mist is revealed to be Skid, an evil dimension-jumping ghost who was last seen at Club Penguin's 2014 Halloween celebration when he possessed Skip and tried to take over the island by deceiving people. Skid attacks the four and imprisons them (except for Skip who slips away to find help) on the 13th floor's rooftop where Hailey is being held. The rest of the PSA shows up siand is captured by Skid, who reveals it was his plan to lure them to him so that he can get rid of them before carrying out his evil schemes. Luckily, Skip shows up at the last moment with the Ghostbusters, who attempt to capture Skid but end up having their souls taken by him. Luckily, Charlie manages to reach one of their proton guns and zaps Skid with it, apparently destroying him.
Approximately four dimensions away, in the world of the Disney film "The Hunchback of Notre Dame", its central villain Judge Claude Frollo and his talking horse are using the internet via Frollo's magical fireplace when they come across "The Clawless Crab of Notre Dame", a parody fanfiction written by Pixie. Angered at his portrayal in the parody as an overweight polar bear, Frollo ignores the horse's warnings that he is overreacting and vows to take revenge on the PSA.
That night, Frollo's self-performance of his song "Hellfire" is interrupted by Skid, who was not destroyed by the proton gun, but rendered unable to return to the penguin world. Frollo makes a deal with Skid to help him get back the energy needed to return to Club Penguin if Skid can manage to send him to the penguin world. Skid zaps Frollo, giving him a limited supply of his ghosting powers that will allow him to generate portals and use telekinesis. After using Frollo's innocent anthropomorphic gargoyle stautes against the dark intensity of Frollo's "Hellfire" performance on YouTube, Skid manages to create an inception paradox, opening a portal that he uses to use to send Frollo to the penguin world.
After traveling through the universes of the Disney movie "Frozen", the "Angry Birds" feature film, the "Star Wars" movie trilogies, the game "My Little Pony: Friendship is Magic", and the TV show "Thomas the Tank Engine and Friends", Frollo arrives in Club Penguin, but accidentally brings a character from each franchise with him: Olaf, an anthropomorphic snowman from "Frozen", Chuck, a talkative and speedy banana-shaped canary from "Angry Birds", R2-D2, an intelligent but accident-prone robot from "Star Wars", Rainbow Dash, a rude and egocentric "Pegasus" from "My Little Pony" and the titular character of "Thomas the Tank Engine", a bipolar tank engine who's personality constantly changes. Frollo uses his telekinesis to prevent them from escaping and imprisons them all in the lighthouse.
Following Skid's instructions, Frollo kidnaps Wingman, Charlie's rainbow puffle, and holds him hostage on the lighthouse with everyone else. Charlie and Pixie come to save Wingman but are captured by Frollo, who sends a message to the PSA HQ declaring that he will only let the two directors go if the entire agency comes to retrieve them. The rest of the agents come armed and try to attack Frollo, but he opens a portal at the last second and sucks everyone into it (except for Wingman) before vanishing into thin air.
Everyone is brought to Skid's home dimension, where Skid demonstrates his power by sucking the life out of R2-D2, and growing bigger and stronger as a result. Everyone splits up and