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.

Sick in bed right before the big Mystery Solvers Club State Finals, Scooby dreams about going to the competition and teaming up with fellow mystery-solver sidekicks Speed Buggy, Jabberjaw, Captain Caveman and The Funky Phantom to rescue their friends from the clutches of the demonic Lord Infernicus.

When Fred invites the gang on his and Daphne's second date, it pushes Daphne into the arms of Obnarb, the leader of an Orc Biker group called the Wild Brood who have come into town. When a break in at the armory happens and a dangerous weapon is stolen, the Wild Brood are the top suspects. It's up to the gang to solve this mystery, save the Wild Brood, and find the imposter Orc Biker.

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.

After being jailed for solving another mystery, the Mystery Inc. gang stumbles upon another mystery: a gruesome monster lurking underneath the town and cocooning everyone who comes near in green goop.

When an exchange student named Mai Le comes to Crystal Cove, she draws the affection of Shaggy. A dinner party hosted by the Blake Family is interrupted by the Red Wizard warning to stay away from the Dragon's Heart which he has sworn to protect at all cost. Later, Mai Le and the gang to come under attack by a White Wizard who is after Mai Le's ring, and the Red Wizard comes to the gang's rescue, but he is too late to save the ring. The Red Wizard turns out to be Mr. Chen, the owner of Chen's Internet Cafe and Tea House. He reveals that with the White Wizard, now in possession of all four rings, is able to open the Jade Dragon's Heart, which is a priceless ruby. Will the gang solve the mystery or is everything not as it seems?

Feeling left out of the group, Velma goes solo to investigate attacks by amphibious "Fish Freaks" in the area around an abandoned oil rig, only to find a friend of her own... in the form of a mermaid!

When Fred's favorite adventurer, Dr. Rick Spartan, starts teaching biology at the Crystal Cove's High School, the gang gets to meet him. Fred tells him that the gang has also been into some terrifying experiences, Spartan immediately invites them to have dinner at his place, where he promises to show them his latest trophy, the cursed Shrunken Head of Squar Gringot. But when its headless body appears and threatens to pursue the professor until the end of his days for plundering its tomb, the gang must find out a way to break the curse.

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.

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.

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.

The gang investigates after Crystal Cove begins suffering from an infestation of deadly insects that targets workers of the company Destroido, the company that makes Shaggy and Scooby's favorite snacks.

When the entire town of Crystal Cove is taken over by Aphrodite's love spell, only Scooby-Doo and the recently-escaped Professor Pericles can save the gang from the spell and solve the mystery. But does Professor Pericles have ulterior motives?

Mystery Inc. has disbanded. Crystal Cove is attacked by a Man-Baby called Crybaby Clown. Mayor Nettles is approached by a mysterious figure who gives her the files on Mystery Inc. while stating that she has to get Mystery Inc. back together.

Velma and Hot Dog Water go to Russia on a mission for Mr E, and bring back an old house which springs legs and runs rampage over town. Meanwhile the gang are looking to replace Daphne and Velma suggests Hot Dog Water.

Fred tries to get Daphne back. Crybaby Clown returns to rob Crystal Cove and kidnaps Daphne as well. Daphne is rescued and agrees to return to the gang. Mr. E tries to re-recruit Angel Dynamite.

Dreamweaver has come to life brainwashing an old group of Crypts and Creepers players (including Sheriff Bronson Stone) by entering their minds while they sleep!

A creature called The Hodag of Horror attacks Crystal Cove; meanwhile, Brad Chiles and Judy Reeves (Fred’s real parents) have suddenly appeared along with a dog whom Scooby has taken a fancy to.

An artist's painting comes to life and attacks patrons of the museum. The gang is asked to solve the mystery so the Art Museum can be saved.

An artist's painting comes to life and attacks patrons of the museum. The gang is asked to solve the mystery so the Art Museum can be saved.

Gary and Ethan are attacked by the Dark Lilith on Mount Diabla and lose the soccer team's lucky soccer ball.

Hebediah Grim, a pilgrim monster is targeting, attacking and judging certain women of Crystal Cove at the lover's hot spot, Lover's Lane.

Snowed in by an avalanche, the gang find themselves trapped in a creepy library.

Deep-sea robots attack Cassidy. The gang helps her solve the case of who is sending them.