A young man and his girlfriend move into the man's old mansion home, where he becomes possessed by a need to control ancient demons.

Four bloodthirsty demons stow away on a truck belonging to the owners of a carnival attraction and, after arriving at the fairgrounds, hole up inside the ride, which becomes a sensation after patrons believe the creatures are part of the show.

A college teacher brings the little creatures back to his campus, where they proceed to terrorize the faculty and students.

While in pursuit of cop Johnathan Graves, his demonic nemesis, Faust, sends his disciple Alexandria to hunt down the amulet that will set him free. Meanwhile, the Ghoulies find their way through an open porthole and onto the streets of L.A., creating madness and mayhem as they search for a way to get back home. As the body count rises, it becomes an ultimate battle between a demonic killer, a rule-breaking cop, and our favorite creatures from the netherworld!