Dr. Phibes and his agents and techies make a DVD of a horror movie with real monsters, and thanks to Robi's new 4-D entertainment system, the monsters invade Shaggy and Scooby's home. A pig named Bacon from a trailer Agent 2 was obsessing about also lounges around, and Scooby and Shaggy work on a way to stop the monsters and Phibes before he can make copies of the DVD.