There is a monster underwater, and on land, there is a heatwave and a drought. Another monster attacks a man in the bathtub, while the Ghostbusters are being interviewed for a celebrity magazine. After Peter's (long) interview, it is Ray's turn, but then the phone rings. It turns out to be Mayor Lenny, who wants to speak to Egon in particular, and reports that all the water in the city appears to be haunted, so they drive off, with the interviewing lady (whose name is revealed to be Alice Johnson) accompanying them.
They find a running, scared crowd and discover they're running from spirits that are flying out of a burst fire hydrant (which Ray thinks may be undines, except undines usually aren't evil). They try to trap them, but they all forgot to bring any traps, so the undines escape and fly away, and the hydrant repairs itself. Alice thought she heard the spirits chanting, "Necksa!", so Egon looks the name up, and it turns out, Necksa is their leader, and a water demon.
The Ghostbusters and Alice go to the river and find more chanting undines, along with Necksa himself. He's mad at the Ghostbusters for interfering with his "children", and Egon tries to point out that his "children" were causing a lot of harm, but Necksa doesn't listen. He reveals that he's been sleeping in the river since before humans evolved, but was woken by the humans draining the river, and now he wants to sink New York and take over. Ray tries to zap Necksa, but he's immune, then he swallows the Ghostbusters but spits out Peter through a blowhole-esque valve.
Peter is sure the others are alive, and gets the Ecto-1 to save them, telling Janine to get Alice to help. At the river, Peter calls for Necksa, who eventually shows up. Peter taunts Necksa into trying to swallow him, luring him into a net. Peter then uses a modified proton pack to suck Necksa's bodily fluids. He turns it off before Necksa has a chance to die, but chews him out and demands he spit out the other Ghostbusters, suggesting that, if Necksa hates humans, he should move to an unpopulated place like Antarctica. Eventually, Necksa sees reason and spits the other Ghostbusters out. Alice is impressed and publishes the story.
This episode provides examples of
- Badass in Distress: Egon, Ray, and Winston get swallowed by Necksa.
- Bullying a Dragon: Invoked — Peter deliberately taunts Necksa into trying to swallow him.
- Can't Get Away with Nuthin': A man is bathing despite the temporary "no baths, only showers" rule, when a monster attacks him in the tub.
- Comically Missing the Point: When Janine berates Peter for telling her to "calm down" despite the many things going wrong, one of which being "Egon, Ray, and Winston got swallowed by a whale", Peter corrects her that Necksa isn't a whale.
- Did You Just Flip Off Cthulhu?: Peter says to Necksa, a powerful river demon, "What's the matter, tubby? Scared?", then later calls him "sucker boy".
- Distressed Dude: Peter has to save his friends from Necksa's belly.
- Evil Laugh: The undines do a shrill, evil chuckle when flying over the humans' heads.
- Evil Sounds Deep: The homicidal Necksa has a deep, gravelly voice.
- Extra Eyes: One undine has three eyes.
- Facepalm: Peter facepalms upon learning Alice will publish his forgetting to bring ghost traps.
- Fantastic Racism: Necksa admits to hating humans (and possibly other land animals).
- Fat Bastard: Downplayed — a man breaks the "no baths, only showers" rule during a drought.
- Flight: The undines can fly.
- Genre Savvy: Peter figures that his friends are alive since he's seen Pinocchio, in which the eponymous puppet survived being swallowed.
- Green and Mean: Necksa, a demon that wants to sink New York, is dark green.
- Heat Wave: The episode takes place on a very hot day. It's so hot, that there's a drought, and Janine is wearing a bikini instead of her usual clothes.
- Immortality: Implied for Necksa, who's millenia old and mentions hating "land-dwelling mortals".
- Mind over Matter: The hydrant repairing itself points to either Necksa or the undines being telekinetic.
- Mythology Gag: Peter mentions Gozer from the movie.
- Nightmare Fetishist: Alice Johnson actually likes going into dangerous situations, since she uses them in her articles.
- No-Sell: Necksa is immune to proton streams.
- No Sympathy: Alice doesn't seem too concerned about Egon, Ray, and Winston being swallowed by Necksa; she just comments that this was the Ghostbusters' last case.
- Oh, Crap!: When Necksa lunges at Peter, he says nervously, "I hope this works!".
- Papa Wolf: Necksa gets mad at the Ghostbusters for attacking the undines, who he refers to as his children.
- Phrase Catcher: The undines chant Necksa's name.
- Pre-Asskicking One-Liner: Before shooting at Necksa, Peter says, "Okay, Moby Dick, chew on this!".
- Red Eyes, Take Warning: Necksa wants to drown every human in New York and his eyes are red.
- Reports of My Death Were Greatly Exaggerated: When Necksa swallows Ray, Egon, and Winston, Alice seems to think they're dead as she refers to the case as the Ghostbusters' last one.
- Rip Van Winkle: Until the drought combined with the humans taking the water woke Necksa up, he'd been asleep for thousands of years, since before humanity.
- Running Gag: Alice keeps changing what she wants Peter to call her.
- Share Phrase: The undines all chant Necksa's name.
- Shout-Out:
- Significant Name Shift: Alice Johnson initially wants Peter to call her "Mrs. Johnson", but switches to "Alice" after he saves her.
- Slapstick: Alice gets drenched in water at one point.
- Smart Ball: Peter invents something, which is usually Egon's (and to a lesser extent, Ray's) area of expertise. Lampshaded when Egon notes it's unusual.
- Speak in Unison: When Peter says, "When there's a job to do...", the rest of the Ghostbusters say in unison, boredly, "We do it."
- Swallowed Whole: Necksa swallows the Ghostbusters whole, but spits out Peter.
- Terms of Endangerment: Peter calls Necksa "old buddy" and later "sweetheart".
- Theme Music Power-Up: The theme tune plays as Peter is facing up against Necksa.
- They Call Me MISTER Tibbs!: Alice Johnson wants Egon and Ray to call her by her first name, but Peter to call her "Ms. Johnson" (though eventually warms up to him calling her Alice).
- Water Is Blue: The river is drawn as blue.
- You Are Fat: Peter calls Necksa "tubby".
