The trail leads to the abandoned Coolsville Cybertech factory, the former lab of the evil genius Jonathan Jacobo (Tim Blake Nelson). Jacobo was a bitter former member of Mystery Inc. who was kicked out for faking monsters and attempting to sell their secrets. In the climax, it is revealed that Patrick Wisely is actually Jacobo in disguise. He plans to use the spectral ray to unleash an army of monsters on the Coolsville Founder’s Day celebration, then destroy the town with a massive monster named the "Evil Masked Figure."
Determined to clear their name, Mystery Inc. investigates. Velma discovers that the monsters are being created by a "spectral ray accelerator" that turns negative energy into real monsters. The gang splits up: Fred obsesses over creating a new, "cooler" Mystery Machine, Daphne tries to become more assertive and investigative, while Shaggy and Scooby struggle with self-doubt and are tricked into joining a support group for wannabe detectives. Scooby-Doo 2- Monsters Unleashed
However, during the gala, a mysterious, masked figure in a black cloak and raven mask unleashes the real, living versions of these classic monsters: the Black Knight Ghost (from Scooby-Doo, Where Are You! ), the 10,000-Volt Ghost, the Pterodactyl Ghost, the Skeleton Ghost, and the zombie miner, Miner Forty-Niner. They attack the museum and steal the secret project of the mysterious "Evil Masked Figure." The gang is blamed for the chaos, and their reputation is shattered. The trail leads to the abandoned Coolsville Cybertech