Shaggy has won a roller coaster design contest, and the gang heads to the amusement park to check it out. However, their fun is cut short when a mysterious monster starts sabotaging the rides.
This episode includes examples of the following tropes:
- Ambiguous Situation: The gang doesn't call the cops on Terry for framing her sister Chris, as well as sabotaging their family's theme park. They ultimately decide to leave it up to Terry's family to determine how she should be punished. Chris runs off to notify their mom about what Terry did, which makes Terry chase after her sister and beg her not to do that. We ultimately don't find out what happens to the perpetrator.
- Artistic License – Law: The titular monster hops on rides more than once to tamper with them while riders are on them, putting them in mortal danger. In one case, a car on the Rocket Coaster ride is derailed from the track and sent flying into the water. Terry was the perpetrator behind the mask, but she doesn't go to jail onscreen; Chris goes to tell their mother to determine a suitable punishment. While this could be explained through Soft Water, the skydiving simulator that almost sliced up Fred, Velma, and Daphne is far more egregious. Fred and Daphne point out that she didn't do anything illegal, it was just rude. In real life, she would've certainly been arrested for attempted murder at the very least.
- Disappointed in You: Chris says this upon learning her sister, Terry, plotted against her.
- Gender-Concealing Writing: The gang goes to an amusement park without knowing anything about its owners other than their names (Chris and Terry) and their fame obtained by building the park's rides. The gang initially assumed that Chris and Terry were men, but it turns that they're girls (and sisters at that).
- Green-Eyed Monster: Terry revealed that she was jealous that she did all the work while her sister got all the credit. Since her sister never bothered doing her fair share, that made it easy for Terry to frame Chris, but that ultimately led to her downfall.Terry: I always did all the work, bringing your crazy designs to life, never getting to build any of my own. Did I ever get any credit or even a "Thank you"?Chris: I never thought about it like that.Terry: You never thought at all. You were easy to frame.Velma: Too easy. That's why tripped you up.
- Hourglass Plot: When the gang arrives, Shaggy, Scooby, and Fred are the ones who are excited about the coasters; Daphne claims that vomiting and calling it fun sounds like a boy thing. After getting on her first ride or two, she gets increasingly obsessed while Fred is more focused on solving the case.
- Karma Houdini: Subverted by Terry. While she avoids being arrested for sabotaging her sister's theme park rides because the group somehow deduce that the rides were only made to look sabotaged but were still completely safe (which doesn't line up at all with her derailing a roller coaster with Shaggy and Scooby on it and almost getting the others killed by a giant fan by removing the safety net), it's implied that she's about to be in big trouble with her parents, since her sister threatens to tell their mom about everything (Terry is last seen running after her, begging her not to say anything). After all, Terry's family could still have her arrested for what she did (or, at the very least, fire her).
- Not Using the "Z" Word: The Roller Ghoster has several similarities to a gremlin, being a furry green monster who tampers with the technology of amusement park rides, but is only ever referred to as a "ghost" despite not possessing any ghostly qualities.
- Orgy of Evidence: As Velma points out, Terry's attempt to frame Chris went awry simply because the clues were too obvious from using Chris' main wrench to leaving a clump of her hair behind.
- Red Herring: Most of the clues point to Chris being the main suspect, but as Velma pointed out, everything seemed way too obvious.
- Samus Is a Girl: Shaggy is shocked to learn the two ride designers, Chris and Terry, are a pair of sisters.
- Shout-Out: When the Roller Ghoster crashes into a tent the stuff animals that fall out are based off Hanna-Barbera characters such as Yogi Bear, Peter Potamus, Huckleberry Hound, Squiddly Diddly, and Atom Ant.
- Throw the Dog a Bone: Eddie spent the entire day being refused entry on any of the rides he wanted to go on due to being too short to ride them. And after the culprit is exposed and caught, he gets told that he also wasn't considered as a suspect because he wasn't tall enough to fit the costume. Seeing how upset Eddie was about height ruining his day at the park, Shaggy allows him on the test ride for the roller coaster he designed with him and Scooby, which Shaggy points out that Eddie isn't too short for. Implying that Shaggy specifically designed it for anyone and everyone who wanted to ride.
- You Must Be This Tall to Ride: There's a running gag involving a small boy named Eddie being told that he is too short to go on certain rides, such as the Sky-Diving Simulator, the Slingshot, and the Rocket Coaster. After the real culprit is caught, he demands to know why he wasn't considered a suspect (as they knew he had a motive)... and Velma points out he's too short for the costume, to his utter frustration. Shaggy then tells him there's one thing he isn't too short for — cut to Eddie, Shaggy and Scooby on the food-based ride that Shaggy had designed for the amusement park.
