Shaggy and Scooby-Doo are being chased by The Plotter and his accomplices. Shaggy wishes that he had never met Mystery Inc., just before crashing through a rotten floor. While unconscious, he dreams of what the world would be like with no Mystery Inc.: overrun with costumed monsters who were never caught.
Shaggy and Scooby-Doo saw him shaking his fist and his cane and them in Shaggy's dream; the "For Sale" signs in Shaggy's dream and the one outside the place where Shaggy and Scooby-Doo fell down into before Shaggy had his dream revealed him to by a real-estate broker.
It's a Wonderful Xmas from Scooby-Scooby-Doooooooooooo. Shaggy takes a tumble while fleeing from an imaginatively conceived masquerade by Pope and McRae. His trip to la-la land has him dreaming a little dream where Mystery Inc. never existed.
Simmons takes a time-honored tradition through the magnifying glass of the sleuth. Despite being consistently scared witless--evidenced by hilarious wild takes from the Shagster, Shaggy quickly learns that it's preferable to a world over-run by flamboyant real estate scammers. Bonus bell ringing for Simmons having Shaggy solve the mystery that led him to the insight.