It is Halloween in the land of Vyond and Ellie is throwing a Halloween party. She has invited RetroMiller, her friends Jamie, Martha, Paul, Mitchell, Keyshia, and many others. The party is going along very well until they realize that the place they are partying at is the old Color Dynamics' studios where Barney and the backyard gang is taped and that it’s haunted by the bear from Barney’s campfire sing-along and the bear has kidnapped Ellie along with her ex-boyfriend Lucas and a new trouble maker named Jiminy the ogre. It’s up to everyone at the party to save Ellie once and for all!