The gang decides to launch an investigation into the existence of a mythical ghost town that is believed to have been populated by alligators.

Strange things continue happening in Crystal Cove, when doorknobs suddenly vanish and a priceless diamond is hidden somewhere. To top it all off, a mysterious Ghost Trucker is also scaring the town.

A Man Crab attacks Crystal Cove beach during a volleyball tournament for Trickell's Triquid diet mixture. The gang must stop him and solve this mystery before the tournament's female players, who the Man Crab has taken a liking to, are put in danger. Meanwhile, Velma gets some relationship advice from Daphne.

The children of Crystal Cove are being turned into monsters by a creature named Que Horrifico, scaring all of the adults in town. As a result, they abandon their children and run for their lives.

Fred becomes the target of a high school crush when new girl Alice May falls for him. However, Alice May is actually a ghost with a reputation for taking guys with her and making them disappear forever.

The Hex Girls, Velma's favorite band, come to Crystal Cove and plan to give the gang a concert. But things go awry when The Phantom, an evil specter, suddenly appears with the intention of permanently taking The Hex Girls out of the music business.

The gang attends the Royal Knights Faire in Crystal Cove, but so does an unexpected guest. A scary-looking gnome is paralyzing everyone wearing pirate costumes at the faire.

When two giant monsters start to attack Crystal Cove, Mayor Jones asks Fred and the gang to help him and the sheriff capture them. Meanwhile, Shaggy has to choose between his relationship with Velma and his friendship with Scooby.

A monster called the Fright Hound starts attacking Crystal Cove and people believe Scooby-Doo is behind it. Could Scooby be the one attacking the city or is someone setting him up?