1. Halloween

While trick-or-treating with his cousin Scott and a friend when he was little, Fred has a scarring experience when he is ambushed by an evil witch near an abandoned cabin. Several years later, Fred and the gang run into the very same witch on Halloween night in another town. As the gang attempts to solve the mystery of the witch, they must also convince Fred that he is incorrect in his belief that a mystery cannot be solved on Halloween night.

2. Scroogey Doo

The gang travels to Britain in 1843-ish and runs into Scrooge who claims he was attacked by the ghost of his partner Jacob Marley and that three more ghosts are coming. The gang agrees to solve the mystery but Velma wonders if she has more potential than just solving mysteries.

3. Some Fred Time

With Fred not sleeping the gang decides it is time for a vacation. However their relaxation is short lived when a monster shark terrorizes the beach. The gang must solve the mystery whilst making sure Fred relaxes and doesn't get involved

4. There Wolf

When Scooby falls sick, the gang immediately rushes him to the hospital, only to discover it is being haunted by a werewolf. The gang must help Scooby and solve the mystery.

6. How to Train Your Coward

Shaggy and Scooby, sick of the monsters and mysteries, leave the Mystery Gang.

7. Worst in Show

The gang decides to go to a dog show in New York, but they soon discover a mystery. With Fred undercover, Scooby trying to win the respect of other dogs, and Velma and Shaggy switching personalities, it's going to be a tough case to crack.

8. Mysteries on the Disorient Express

The gang is on a 3-day trip on a train, but when 8 monsters from different parts of the world appear, it's time for action. The monsters are the Grim Reaper, a Mummy, Tzitzimitl, Haniver, a Manticore, Hemogoblin, Tengu, and Tarasque.

9. The Curse of Kaniaku

Fred tries to solve a 700-year-old mystery in Japan; Daphne becomes a viral sensation.

10. Vote Velma

Velma runs for mayor to bait the ghost that has returned to a town and scare the mayoral candidates.

11. In Space

A virus infects an asteroid mining crew one by one, turning them into evil skull-headed aliens.

12. Doo Not Disturb

To escape a snowstorm, the gang checks into a creepy hotel run by a man with strict rules.

13. Silver Scream

The gang tours an old Hollywood Studio, but they soon uncover a mystery concerning the ghost of a silent film comedy star who has returned to make sure his recently discovered final film is never seen.

14. Fright of Hand

Fred gets to live out his childhood dream of being a stage magician when a mutant rabbit monster terrorizes a magic club.

15. Greece is the Word

The gang gets trapped in an ancient Greek palace, where they must find a scroll to escape.

16. American Goth

Shaggy is surprised to see his old childhood first crush has become a goth; embarrassed that he hasn't changed at all, Shaggy attends a goth party with the gang.

17. Omelettes are Forever

The gang gets caught up in international espionage when they cross paths with British secret agent, Jenny Vex, and must help her complete her dangerous mission.

18. Ghost in the Mystery Machine

Fred's worst nightmare comes true when an evil spirit possesses the Mystery Machine and turns his beloved van into an unrelenting monster.

19. Naughty or Ice

Daphne brings the gang to a fancy ice hotel where a new exhibit of ice age artifacts is opening; things heat up when a frozen Ice Man goes on a rampage inside the hotel.

20. Night of the Upsetting Shorts

The gang heads to Shaggy's beloved grandmother's Florida retirement home, where they learn a crazed ape man has been frightening the elderly residents.

21. Junkyard Dogs

Scooby Doo runs into an old kennel mate from the rescue shelter, Axel, who is now a state-of-the-art, highly trained K-9 police dog.

22. Protein Titans 2

When a successful video game company tries to convince Velma to work for them in San Francisco, the gang becomes embroiled in the mystery of a video game villain.

23. World of Witchcraft

The gang are caught in a witch's revenge for the Salem witch trials.

24. Professor Huh? Part 1

The gang investigate the mysterious Professor Huh?, who pits them against another rival gang led by a childhood friend of Fred.

25. Professor Huh? Part 6¾

The gang investigate the mysterious Professor Huh?, who pits them against another rival gang led by an old childhood friend of Fred.

26. Pizza O'Possum's

Shaggy drags the gang to an arcade where the animatronic mascot has apparently come to life.

27. The Curse of Half-Beard's Booty

At a seafood restaurant, the ghost of a legendary pirate, Half-Beard, has been scaring away the customers. Captain Cutler joins the gang on a treasure hunt at Double-Cross Cove where Half-Beard's treasure is supposedly buried.