Rudy buys a hot dog for Slimer, but it's too expensive, and Slimer eats it before it can be returned. The hot dog guy threatens to call the police on Slimer and Rudy if they can't pay, scaring Slimer, who then (along with Rudy) sees a monkey in clothes being paid for his cuteness. The monkey then steals the man's wallet and gives it to his owner, who keeps it, along with other wallets.
Rudy has a plan to pay the hot dog man and have plenty of money for themselves: Rudy builds an organ-grinding machine like the monkey's owner had, and tells Slimer to be his "monkey". Slimer refuses until Rudy promises him ice cream in whatever flavour he wants.
While Rudy dresses Slimer in a shirt and hat and has him pretend to be a monkey, the organ grinder, jealous of the competition, sends the monkey over to flip a switch marked "uncool". This causes the machine to go haywire when turned on.
Rudy flips a second switch, labelled "cool", which plays music, and Slimer dances. This lands them a lot of money, but the organ-grinder tells the police that Rudy and Slimer's performance is illegal. Rudy tells the cop that Slimer is a ghost, but the cop doesn't believe him. Rudy tells him to look monkeys up in a book, so the cop does, and realises that Slimer is not a monkey since he isn't brown and has no tail. Upon looking up ghosts in the book, he decides that Slimer must be a ghost after all.
Rudy points out the thieving monkey, so the policeman goes to arrest him. The organ grinder tries to pretend the monkey is a dog, but the cop isn't buying it and arrests the organ grinder.
This episode provides examples of
- Baby Talk: A man calls the monkey a "cute itty-bitty wittle guy".
- Blatant Lies: When caught by the police, the organ grinder claims his pet monkey is actually a dog.
- Contrived Coincidence: The cop just happens to be carrying a book that has information on both monkeys and ghosts.
- Extreme Omnivore: Slimer's ability to eat everything regardless of whether it's food is apparently a trait all ghosts have, according to the book the police guy reads.
- Flat-Earth Atheist: The police guy doesn't believe Rudy when he says that Slimer is a ghost, despite the fact that Slimer is a flying, green entity.
- Food as Bribe: When the promise of the money isn't enough to convince Slimer to be a "monkey", Rudy promises him ice cream in any flavour he wants.
- Forgot About His Powers: Slimer fears being imprisoned (in a normal human jail) for not paying for his hot dog, apparently forgetting that he can phase through walls.
- Fully-Dressed Cartoon Animal: The monkey wears a shirt, pants, gloves, shoes, and hat.
- Hey, Let's Put on a Show: Rudy thinks that the best way to quickly make money is to have Slimer perform while pretending to be a monkey.
- Imagine Spot: Slimer briefly imagines himself in prison when the hot dog guy threatens to call the cops.
- Institutional Apparel: In Slimer's daydream of him in prison, he wears a black and white striped prison uniform.
- Intelligent Primate: The monkey seems to understand English.
- Loophole Abuse: It's illegal to have a performing monkey, so Rudy has a ghost perform while pretending to be a monkey.
- Mischief-Making Monkey: The monkey steals wallets and he also sabotages Slimer and Rudy (albeit on his owner's command).
- Mythology Gag: Rudy calls Slimer by his "spud" nickname from the movie.
- Paper-Thin Disguise: Slimer is still green in his monkey disguise.
- Pun:
- When expressing disbelief that Slimer is a ghost and not a monkey, the policeman says, "Don't try to make a monkey out of me, punk!".
- At the end, the narrator says that the organ grinder being arrested for having his monkey steal wallets proves that "monkey business" doesn't pay.
- Pun-Based Title: The title puns on the expression "monkey see, monkey do".
- Silly Simian: The monkey does a goofy little dance when mocking Slimer and Rudy.
- Stock Animal Diet: The information in the cop's book on monkeys includes "eats bananas".
- Thieving Pet: Exploited — the monkey steals wallets, which his owner keeps.
- Tonuge Out Insult: The monkey sticks his tongue out at Slimer and Rudy after the organ-grinding machine goes crazy.
- Unusually Uninteresting Sight: Nobody seems to notice that Slimer is green; they just applaud him as if he were a regular performing monkey.
- Wingding Eyes: Slimer gets dollar signs in his eyes when Rudy promises "mucho money".
