Trouble's afoot when the gang goes to a games tournament to watch a checkers champ face off against a computer -- and the computer comes to life!
Shaggy and Scooby are playing checkers when Fred goes over a speed bump (faster than he should). Their game is over as a result, and the duo argue until Fred arrives at Plonck's Checkers Challenge, where the gang realize someone named Ron Ripsnishes is playing, and that they're there to watch him play one of the most important matches in his career. They meet Sawyer Finn, who's the president of the International Checkers Federation. Both him and an unknown woman proceed to point out who his opponent will be: a green alien-like creature named Victor.
The unknown woman is revealed to be Shelby Chipworth, a young computer programmer, who reveals what Victor's name stands for: Virtual Interactive Checkers Tournament Opponent Response software, a program she claims she's been working on for years. Velma claims computer checker games have been around forever and proceeds to ask Shelby why she feels so special. Shelby then leads the gang to a table where she opens up a laptop and types some commands (it's not revealed which). Shaggy then plays a game with Victor, revealing what it's programmed to do. Shelby disappears into the crowd, which is dressed in checker outfits. Shaggy and Scooby leave to go get some food but unexpectedly startle a man, which leads themselves to being startled.
They find he's eating a bag of chips, and does so when he's nervous or upset. Shaggy and Scooby reveal they like to do the same before they begin tiptoeing away from the scene after realizing the bag of chips is empty. The man then calls them back. He reveals he's spent too much money on the game and may have to declare bankruptcy. He reveals himself as Everett Plonck, the sponsor of the event, and the one who put up $1M for a gold trophy. This shocks Shaggy and Scooby, who say that's a lot of food. Everett pulls out a checkers set and a rule book, which he says he got when he was 7 years old, and that he's loved the game all his life and has dreamed of being part of something like the Checker Challenge. He'd hate to see his dreams go down and doesn't know what to do. He thanks Shaggy and Scooby for listening and hands them a bag of potato chips, which they munch on as the rest of the gang arrive. Shaggy explains his and Scooby's encounter with Everett Plonck. Just as they finish, someone in a crowd shouts that "he" is here. Velma thinks Ron Ripsnishes has arrived.
They see a man in a blue suit and an older man holding a laptop walk by, with the former explaining to the latter how Victor is much smarter than any other computer he's faced against. Shaggy and Scooby dress in checkers gear and show off to the rest of the gang when they wonder where they are. They have the rest of the gang put on checker wear for themselves. They then follow a crowd into a large auditorium.
They notice the auditorium is largely empty for a checkers tournament. They sit down in some empty seats close to the stage as the lights dim and Sawyer Finn steps out onto the stage, welcoming everyone to the event. They notice everyone clicking checkers together and realize it must be how everyone applauds at checkers events. Ron Ripsnishes is about to make his first move when Victor comes to life and steps onto the stage. He causes chaos and empties the auditorium and stage until the gang is left. The gang decide they've got a mystery to solve.
The gang go on the stage and search around. Shaggy notices a checker piece moving by itself on the board and gets startled. Scooby gets startled too. Velma notices it's a black box with flashing lights on it, which at first turns out to be a clue. It appears it was hooked under the table to allow Victor's checkers to move. Velma then explains what the real clue is: a black oval object that fits neatly in the palm of her hand. It has a small ball sticking out through the bottom. It's revealed as a wireless mouse, something you'd use on a laptop computer. Shaggy assumes a laptop could catch the villain allowing the gang to get out, but Daphne explains how it won't be easy. Velma and Fred clarify that they need more clues, which Shaggy feared.
Shaggy and Scooby journey into the lobby and encounter Victor, who chases them around the lobby until they hide behind a row of potted palm trees. They poke their heads out and scare Daphne and themselves, before explaining to the rest of the gang how Victor was chasing them around the lobby. Velma and Fred reveal a book that Victor dropped, which is a rule book just like the one Shaggy and Scooby had seen earlier. It turns out to be another clue. The gang then have their final clue when they notice Shaggy and Scooby eating potato chips off the row of palm trees.
The gang decide that as a trap Shaggy and Scooby are to sit on the stage and play checkers while Fred, Daphne, and Velma grab a banner to toss over Victor. Shaggy ends up in the banner, but Victor is still caught by tripping on a knocked-down potted palm tree.
Victor is unmasked as Everett Plonck. He, Shelby, and Ron had access to laptops and each had a motive for wanting the gold trophy. He needed help with checkers, unlike Ron, who was a pro at the game and didn't need a book such as the one Everett showed to Shaggy and Scooby. Only one of these suspects had been eating potato chips, and once the gang realized who it was, they were ready to set a trap. He was bankrupt and couldn't sit around watching the gold trophy slip away, and wanted to use the gold in the trophy so he could rebuild his company. However, Sawyer reveals the real gold trophy had been in his safe ever since he'd brought it in, causing Everett's face to fall. As Everett is taken away in handcuffs (presumably into custody), Ron pokes his head out through a broom closet door and, coming out, reveals he hid in there once Victor showed up. Ron notices Scooby in a giant checker costume and is surprised. Scooby ends the case with his usual "Scooby-Dooby-Doo!" cheer.
|Shelby||She wanted publicity and her program "coming to life" would be big news.|
|Everett Plonck||He had given a golden trophy to the contest that he couldn't afford.|
|Ron Ripsnishes||Fear of losing to a computer program.|
|Everett Plonck as Victor||To steal the trophy, so he could use the gold in it for money to rebuild his company.|
Scooby-Doo! and the Gruesome Goblin
Scooby-Doo! and the Hoopster Horror