Dr. Rick Spartan returns to Crystal Cove to thwart the evil Gluten Demon, a creature that terrorizes people and eats anything that isn't a fruit or a vegetable.
The episode provides examples of:
- Acrofatic: The Gluten Demon is very agile for a monster of its size. Also, Shaggy and Scooby after their eating binge, once they manage to stand up, that is.
- Adults Are Useless: Averted with Cachinga, subverted with Rick Spartan.
- Balloon Belly: Subverted. In most other Scooby Doo media, this is usually the end result of Shaggy and Scooby going on an eating binge. Here the two of them are presented as morbidly obese rather than just having swollen stomachs when they're done. They also somehow grow about ten feet tall.
- Big Eater: The Gluten Demon, as well as Shaggy and Scooby which is taken to the extreme when the two are ordered by Fred to devour most of the gluten-retaining food in Crystal Cove in order to stage a trap for the Demon.
- Francilee Jackson as well, given she IS the Gluten Demon and her entire plot revolved around literally eating all other restaurants in Crystal Cove out of business.
- Breather Episode: Subverted. The main plot about the Gluten Demon distracts the viewers from the Mr. E/Pericles power struggle, up until the ending.
- Clueless Mystery: Most of the clues about the Gluten Demon are found off-screen, but since this is mostly a Breather Episode that might've been intentional.
- Even Evil Has Standards: Mr. E is prompted to try and take control back from Pericles because he feels Pericles is becoming too unstable. Unfortunately, E assumes Brad and Judy share his standards, but they don't.
- Evil Versus Evil: Pericles and Mr. E. Following the events of the previous episodes, the alliance between the two breaks down after E decides that Pericles has become too insane to work with and tries to oust him from Destroido. Unfortunately for E, Pericles is one step ahead and poisons Mr. E with mutated cobra venom, which he can release in small doses whenever he feels like to keep E in line.
- Faking the Dead: Francilee.
- Gluttony Montage: Shaggy and Scooby's eating binge.
- I'm a Humanitarian: The Gluten Demon eats Francilee Jackson in the first five minutes of the show. Subverted though, because the Demon is Francilee.
- Kevlard: The Gluten Demon, Shaggy, and Scooby become so bloated they're capable of being thrown through walls, beaten with telephone poles, and tossed on top of cars without feeling a thing.
- The Mole: Mr. E finds out too late that Brad and Judy were more loyal to Pericles and alerted him to E's plans for a coup, prompting Pericles to inject E with the cobra venom.
- No Body Left Behind: Francilee was devoured whole by the Gluten Demon, though this is subverted since she was the Demon and staged the whole thing.
- No Celebrities Were Harmed: Francilee is once again presented as a parody of Paula Deen, especially when she reveals that her latest dish is loaded with butter, bacon, and mayonnaise with butter sauce.
- Nutritional Nightmare: The new dish Francilee was gonna unveil was some sort of disgusting pasta entree containing a ridiculous amount of butter, bacon, bread, mayonnaise, and butter sauce.
- Plot Allergy: Francilee is allergic to anything remotely healthy.
- Reasonable Authority Figure: Cachinga lends a big hand in solving the mystery alongside Daphne and Velma.
- Red Herring: Albrecht J. Schwartz has the same A.J.S. initials found by Velma, Daphne, and Cachinga, which leads the viewers to think he is the Gluten Demon destroying property for the sake of insurance fraud.
- Stout Strength: The Gluten Demon is massively strong and destructive, as evident by all the property damage it inflicts when it raids for food. Shaggy and Scooby use their bulk from their eating binge to take the Demon on in a wrestling match and manage to defeat it.
- Temporary Bulk Change: Shaggy and Scooby both become morbidly obese as a result of their eating binge. Becomes an odd sort of Chekhov's Skill when the Gluten Demon shows up for the trap, because the two are now big enough and strong enough to take the monster on after it swats away Fred, Rick Spartan, and Cachinga like nothing.
- Took a Level in Badass: Shaggy and Scooby become much more proactive after the Gluten Demon knocks out Fred, Cachinga, and Rick Spartan, and then tries to kill Daphne and Velma. Take note this is after they went on a gigantic eating binge and become quite obese, to the point that they "were too full to be scared" when the Gluten Demon showed up for the trap. They then engage in a pseudo sumo wrestling match and take the Demon down using their bulk.
- Took a Level in Jerkass: Francilee Jackson from Web of the Dreamweaver as the Gluten Demon. Following her previous appearance, her career was ruined after the lies about her cornbread stuffing were exposed. Her plot was to drive every other restaurant in Crystal Cove out of business so she could reopen hers with no competition.
- Two Lines, No Waiting: Averted. The Mr. E/Pericles plot thread has nothing to do with the gang dealing with the Gluten Demon.
- Weight Woe:
- Francilee eventually gets so fat from eating so much food the police have to roll her away into custody.
- Subverted with Scooby and Shaggy, who are initially too fat to stand on their own and can't fit into the Mystery Machine, but have no problem moving once they stand up.
- Pericles: <tortures Ricky with by pressing the remote control button on Cobra larvae> Oh, Ricky, Ricky, my loyal Brad, and Judy told me of your little mutiny. So, last night while you were asleep, I put mutated cobra larvae in your spine. Every time I press this button, a little venom is released. So, as you can see, or feel, I'm still very much in control. You do as I say. First, we steal the Planispheric Disk from the kinder, then we destroy them. <Evil Laugh> WE DESTROY THEM!
