Slimer is cosplaying as a superhero named Mega Man, with Fred cosplaying as his dog . However, when trying to show off, Slimer crashes and makes a mess. Peter enters in a vampire costume and asks what happened. Slimer apologises for his "boo-boo", but Peter forbids Slimer from trick-or-treating until the room is clean. He leaves, and Slimer sadly wishes Fred (who is allowed to go trick-or-treating) a happy Halloween.
Dweeb dresses as Slimer (wearing a home-made inflatable costume). He then reveals a lounger he invented that was designed to send ghosts back to the spirit world. He accidentally sends himself there instead, but luckily for him, he calls out for Elizabeth just as he's disappearing, who sends him back. He then plans to get Slimer by going out under the guise of trick-or-treating (with Elizabeth dressed as a generic ghost) but Mrs. Dweeb yells at him to instead answer the door for the trick-or-treaters while she watches TV.
Slimer is cleaning up the mess, with Fred having chosen to stay behind and help him. Slimer decides the cleaning is taking too long, so he spins like a tornado (which Mega Man apparently does) and puts everything in the closet. Peter allows Slimer and Fred to trick-or-treat and they leave. Peter then tells Slimer and Fred not to eat any of the candy until he checks it, but then everything falls out of the closet.
Dweeb and Elizabeth arrive at the firehouse, and prepare to wait for Slimer to come out, but instead find Peter yelling at him to clean the room again properly. Meanwhile, an ocean liner drops a crate, out of which Goolem and Zugg emerge. They decide to get revenge on Slimer for sending them to the South Pole twice by scaring him away so he never returns.
Dweeb cleans the room, while pretending he's the real Slimer (and Peter is somehow fooled), then tries to steal some Crunch bars, but Peter scolds him (still thinking Dweeb is Slimer) and tells him they're for the "other" kids. Dweeb then leaves, and he, Elizabeth, Slimer, Fred, Goolem, and Zugg intercept each other, but Goolem and Zugg also think Dweeb is the real Slimer.
They grab him, and he tells Elizabeth to attack, but she's too scared to. Zugg tries to remind "Slimer" who he and Goolem are by tugging on him, but accidentally pulls the mask off, making them realise he's not Slimer. Dweeb introduces himself, gives them his business card, and walks off (the rest of his costume having fallen off) and then Elizabeth grabs the real Slimer by his boots.
His costume falls off, so now all four villains are chasing Slimer. Dweeb catches Slimer in a box then drives off, with Fred chasing the van. Goolem and Zugg then decide to go to Dweeb's house (using the business card) to catch Slimer.
Dweeb and Elizabeth arrive home, with Fred having followed them, and Mrs. Dweeb berates her son for having been away. Dweeb tries to send Slimer back to the spirit world, but Slimer reappears. Dweeb tries doubling the power, but this causes a blackout. Mrs. Dweeb then demands Professor Dweeb fix her TV.
He goes onto the roof and tries to fix the antenna, but has trouble. Fred enters and scares Elizabeth away, then saves Slimer, but then Goolem and Zugg show up. Slimer pretends to let Goolem and Zugg win and tricks them into sitting on the lounger by begging to keep it, so they're sent to the spirit world when Dweeb finishes fixing the antenna. Dweeb is sent away along with them, and they all appear on Mrs. Dweeb's TV.
This short provides examples of
- Accessory-Wearing Cartoon Animal: Fred wears a Viking's hat as his costume.
- Batman Gambit: Slimer tricks Goolem and Zugg into sitting on the chair by making it seem special by begging to keep it.
- Bedsheet Ghost: Elizabeth's ghost costume is just a little white sheet.
- Big "SHUT UP!": Mrs. Dweeb yells at Professor Dweeb, "Now, quiet!".
- Blowing a Raspberry: Elizabeth blows a raspberry at Dweeb to let him know that she doesn't care what his greatest invention is.
- Brought to You by the Letter "S": The illustration of "Mega Man" wears an "M" on his onesie.
- Circling Birdies: Slimer sees stars when he crashes.
- Continuity Nod: Goolem and Zugg complain about being sent to the South Pole again (in "The Dirty Half-Dozen").
- Copycat Mockery:
- When Peter says that the Crunch bars are "for the other kids", Dweeb says, "Those are for the other kids! Na ni na ni na na! Na ni na ni na na!"
- When Mrs. Dweeb says, "Norman, don't make me come up there!", he parrots the line in a mocking voice and scoffs.
- Distressed Dude: Slimer ends up strapped to Dweeb's interdimensional chair.
- Failed a Spot Check: Peter, Goolem, and Zugg mistake Dweeb in costume for the real Slimer despite him having a visible face through his mask and being human-sized, then Dweeb mistakes Slimer in costume for a kid despite him levitating and being green.
- Food End: At the end, Slimer and Fred eat their candy.
- Forgot About His Powers: Slimer can phase through walls, yet he gets caught in the tennis net.
- Genius Sweet Tooth: Dweeb is revealed to love Crunch bars.
- Halloween Episode: The episode takes place on Halloween night.
- Happy Dance: Dweeb does a little dance upon catching Slimer.
- Heroic Dog: Fred is the one to save Slimer.
- Idiot Ball: Peter mistakes Dweeb in his Slimer outfit for the real Slimer.
- Instantly Proven Wrong: Dweeb says to Elizabeth, "Naturally, you're dying to know what's my first greatest invention?". Elizabeth blows a raspberry.
- Irony: Despite being ghosts, Goolem and Zugg are scared by two little kids in costume.
- I Surrender, Suckers: As part of his trick to Goolem and Zugg, Slimer
- Loophole Abuse: Mrs. Dweeb forbids Professor Dweeb from trick-or-treating, so he goes out anyway because it's a scientific mission, not trick-or-treating.
- Mistaken Age: Dweeb mistakes Slimer in costume for a child.
- Mistaken for Undead: Inverted when Dweeb mistakes Slimer for a living child.
- Mistaken Identity: Peter, Goolem, and Zugg mistake Dweeb in a Slimer suit as the real Slimer.
- Mocking Sing-Song:
- Dweeb sings, "Na ni na ni na na!" to Peter.
- Slimer babbles mockingly to Dweeb to the tune of "Ring Around the Rosie".
- Mythology Gag: Peter calls Slimer by his "spud" nickname from the movie.
- Offscreen Crash: We don't actually see the crash Slimer caused — we just hear it and see the mess it left.
- Oh, Crap!: Slimer says, "Uh-oh!" when his costume falls off.
- Quaking with Fear: Elizabeth shakes in fear of Goolem and Zugg.
- Revenge: The title refers to Goolem and Zugg trying to get revenge on Slimer for sending them to the South Pole twice.
- Say My Name: Peter yells, "SLIMER!" upon discovering that he stuffed the items into the closet.
- Slapstick: Dweeb has trouble balancing on the roof.
- That Liar Lies: When Dweeb claims he was just walking Elizabeth, Mrs. Dweeb yells, "Baloney!".
- Toilet Humour: One of the things that flies out of the closet is a toilet.
- Wild Take:
- Peter's eyes bug out when everything falls from the closet.
- Slimer's eyes bug out when Goolem and Zugg pop out of the trash bins.
