The gang accidentally gives Scooby the cold shoulder. Feeling they no longer need him, Scooby runs away. Realizing how cruel they were, the gang goes on a city-wide search for Scooby.

The Gang goes to the Coolsville amusement park. Shaggy and Scooby are excited because they will be the first ones to ride Monster Mountain - a giant roller coaster - for earning the most raffle tickets. Will they survive the emergence of a terrifying ghost clown?

Fed up with Freddy always blaming Red Herring for each mystery, the gang orders him to try to survive with out blaming Red Herring for each crime.