The Ghostbusters are driving to a case, but Walter Peck and his coworker Calahan are tailing them in their own car. While the Ghostbusters are attacking a ghost that's invading a formal party, Calahan spies on them, while Peck declares he will prove the Ghostbusters are frauds. He then sees Slimer, who coats him in slime, then the Ghostbusters trap the ghost at the party.
Later, Peck calls the Ghostbusters, lying that a ghost is haunting a government laboratory, in an attempt to get them arrested for spying. However, when they get to the lab, Egon determines that it is haunted after all, and they trap the ghost and are hailed as heroes. Peck then gets another idea for messing with the Ghostbusters after seeing Slimer.
Peck and Calahan later arrive at the firehouse and try to catch Slimer in a net. He escapes and tells Janine, then the Ghostbusters run up and recognise Peck. Peck claims to be from the BUFO (Bureau of Unidentifiable, Flying Organisms) and forces them to hand Slimer over or else he'll shut down the building. Seeing as Lenny is too busy, the Ghostbusters decide to retrieve Slimer on their own.
The scientists study Slimer, and they can't determine what he is, just that he isn't an animal, plant, or rock. Peck says that if they don't know what Slimer is, he could be dangerous, so he has them destroy Slimer with a cyclotron. As he's put in the cyclotron, the Ghostbusters and Janine use a device on their car to jump the fence, then sneak into the laboratory.
When they get in, Egon tries pressing a button to turn it off, but it doesn't work. Peter demands Peck shut the cyclotron down, but he claims he's forgotten the code. Then, Egon suggests that everyone fire their proton packs at the device to bend the cyclotron's magnetic field, and it works, but Slimer is gone. They think he's lost forever, but then he comes back. The general then thanks the Ghostbusters, fires Peck and Calahan, and and awards Slimer with a medal.
This episode provides examples of
- Accidental Truth: Peck tries to lie that the lab is haunted to get the Ghostbusters in trouble, but it turns out that it is.
- Ate It All: Slimer eats all the food at the party.
- Balloon Belly: Downplayed twice, when Slimer eats a large amount of food and ends up looking a little pudgier than normal.
- Batman Cold Open: The guys take on a two-headed ghost trashing a fancy penthouse party.
- Disney Death: Towards the end, it seems like Slimer has been destroyed, but he's fine.
- Distressed Dude: Slimer is threatened to be destroyed with a cyclotron.
- Ectoplasm:
- Several ghosts cover doors they pass through in slime.
- Slimer gets slime on Walter Peck and all over the laboratory.
- Electromagnetic Ghosts:
- The ghost at the government lab causes the electrical equipment to malfunction.
- Slimer causes one of the scientists' device to spark.
- "Eureka!" Moment: Peck when he realizes he can stick it to the Ghostbusters by using his authority to take Slimer away.
- Everyone's Baby Sister: Peck decides that the best way to get revenge on the Ghostbusters is to have Slimer harmed or destroyed.
- Five-Second Foreshadowing: The Ghostbusters are tricked by Peck's false call into entering a very secure lab so that they'll get arrested. As it happens, two scientists are trying to figure out why the lab's equipment is behaving unusually. The second the guys enter the room, Egon's PKE meter starts going off. There really is a ghost there.
- Flat "What": The scientist in the wheelchair has this response, when Egon reports there really is a ghost hiding somewhere in their lab.
- From Bad to Worse: Not only does the red button not turn the cyclotron off, it speeds it up.
- Happy Dance: Several partygoers at the beginning dance for joy when the Ghostbusters catch the blue ghost.
- Intentional Mess Making: The ghost at the beginning throws things around for fun.
- Irony: Not only did the government scientists not have the Ghostbusters arrested, they actually lauded them for taking away the ghost Peck didn't realise was there.
- Labcoat of Science and Medicine: All the scientists at the labs wear lab coats.
- Mythology Gag: Several references to the original movie are made — Peck wants revenge for the Ghostbusters' actions in the movie, and Slimer is referred to as a "little spud" (which is what Ray called him in the movie) several times.
- Out-of-Character Moment: In the shower, the normally no-nonsense Egon sings a cheerful song.
- Platonic Declaration of Love: When the Ghostbusters and Janine think Slimer is gone, they say they love him.
- Platonic Kissing:
- Slimer kisses Janine just before leaving.
- Discussed when Peter says he'll miss Slimer's wet kisses.
- Rage Breaking Point: After Peck loses the paper with the code for shutting down the cyclotron, Peter is done putting up with his nonsense.Peter: [grabbing him] I'm through playin' games, Peck! What's the code?!
- Revenge: Peck wants to get his own back at the Ghostbusters for what they did before.
- Revenge Before Reason: Peck's new job is way better than his old one, giving him substantially more power and authority. He throws it all away in a vain attempt to get back at the Ghostbusters.
- Revenge by Proxy: With his effort to frame the Ghostbusters having failed, Peck uses his authority to take away their Team Pet just to spite them.
- Rhymes on a Dime: When asked how he's going to get even, Peck simply says, "I have a plan, Callahan."
- Say My Name: The Ghostbusters and Janine cheerfully shout Slimer's name in unison when it turns out he's still around.
- Singing in the Shower: Slimer and Egon sing in the shower together.
- Smart People Wear Glasses: Downplayed — some of the scientists are shown wearing glasses.
- Smorgasbord Test: The scientists lay out numerous foods to determine which of them Slimer will eat. Slimer, naturally, eats all of them.
- Speak in Unison:
- When Winston wonders if the jump mechanism on the car was "a tad too high", the rest say, "Only a tad?" at once.
- When Slimer comes back, the Ghostbusters and Janine say, "Slimer!" in unison.
- Theme Music Power-Up: The main theme plays when the Ghostbusters deactivate the cyclotron.
- We Meet Again: Peck when showing up at the firehouse to take Slimer away.Peck: Remember me, Ghostbusters?
- Wilting Odor: At the end, Slimer has such bad breath, it knocks some men out.
