Spongebob Squarepants is easily Nickelodeon's most beloved series, but, while most episodes were happy-go-lucky, these 15 were downright nightmarish.

Nickelodeon's most popular cartoon, SpongeBob Squarepants, is filled with episodes that evoke an illogical, goofy sense of humor. Set in the underwater town of Bikini Bottom, it revolves around fry-cook SpongeBob and his misadventures with his friends. However, underneath the simple wit, the show can get meta at times, with genius references, and even subtle adult jokes every now and then.

For a kid's show, a few episodes can also get dark or disturbing as compared to the general silly tone. These can be unintentionally terrifying for a few children, while others also include intentional parodies of horror films.

Updated on May 6th, 2021 by Tanner Fox: As ridiculous as it may seem, the Spongebob Squarepants series continues to feature increasingly warped and weird plot points and narrative elements, and the show has only grown more strange and vaguely horrifying as it's gone on. From a Hunter S. Thompson-esque surrealist jaunt through a clarinet forest to an actual reference to the infamous "Red Mist" internet creepypasta, there are plenty of creepy Spongebob episodes yet to be discussed. Having aired for more than two decades and showing no sign of slowing down, we have to wonder what wacky and wild things may hit the airwaves in the future.

15 A Pal For Gary

SpongeBob can't bring his pet snail, Gary, to work. Concerned about his loneliness, he gets him another snail friend called Puffy Fluffy. Puffy turns out to be quite a bully, harassing Gary at any moment when they are alone. SpongeBob still believes that Gary is the troublemaker and not Puffy.

Puffy ends up turning into a large reptilian monster of sorts and even attempts to eat Gary at one point. SpongeBob finds his house in a mess and still feels all of this might Gary's undoing out of jealousy from Puffy. The slug-like appearance of Puffy's final version along with its pointy teeth and Sarlacc-like tongues might be scary for younger viewers.

14 Squidward In Clarinetland

In this season seven episode, Squidward is eager to protect his clarinet from the unruly Krusty Krab clientele before a recital, opting to store it in a locker begrudgingly provided by Mr. Krabs. Unfortunately, SpongeBob takes it upon himself to renovate the locker, transforming it into a twisted, unreal maze that seems to have no end.

To reclaim his instrument, Squidward treks through a clarinet forest, gets swallowed by a giant eagle, and chases SpongeBob through the outer reaches of space before eventually reaching his recital... from which SpongeBob's antics promptly scare him away.

13 The Splinter

A splinter gets stuck in SpongeBob's thumb during work. The usually-squeamish SpongeBob refuses to take it out, leading to further infection. For most of the episode, viewers get to see the disgusting image of the pus-filled wound that only increases in size.

Patrick pretends to be a doctor to cure the injury by adding a dumpster's toxic waste. The swelling only increases and gets infected. Finally, Mr. Krabs removes the splinter as the swelling bursts with liquid pus. It's an episode that puts gross-out humor and outright disgusting imagery at its forefront, and it's an unpleasant watch from beginning to end.

12 Squid's Visit

SpongeBob can be quite a nuisance for his neighbor Squidward, who considers himself to be intellectually superior to any other Bikini Bottomite. It's for this reason that Squidward takes pride in his taste of art and his modernist home design. SpongeBob desperately tries to invite him to his own pineapple house, an invitation that Squidward continuously rejects.

Hellbent on inviting Squidward, the sponge ends up stealing his vacuum. Squidward leaves his dinner in the oven and angrily enters the pineapple. However, to his surprise, he finds Spongebob to be so attached to him that he has redesigned his entire home to match that of Squidward's. Meanwhile, his own house is destroyed by a fire, as the oven was switched on. Hopeless and distressed, he ends up staying with SpongeBob.

11 Ink Lemonade

By 2017, the once-beloved Nickelodeon series had really flown off the rails, and this season eleven episode epitomized the weirdly offputting quality many of its most recent installments have.

In this episode, SpongeBob and Patrick discover that Squidward's Ink actually doubles as a delicious beverage, though he can only produce it when he's scared. What follows are various attempts to frighten Squidward, with Patrick going so far as to peel the flesh from his body, exposing his organs in a grotesque act that certainly wasn't suitable for younger audiences.

10 Planet Of The Jellyfish

In "Planet of the Jellyfish," SpongeBob and Sandy engage in combat with villainous jellyfish known as "jelliens" that clone the inhabitants of Bikini Bottom. The premise is clearly a reference to Invasion of the Body Snatchers, while the title can be a reference to Planet of the Apes or Planet of the Vampires.

The creepy part is the creation of the jelliens; a jellyfish-like alien with black eyes consumes a jellyfish and spits out a pink goo which turns into a hybrid of the monster and its previous jellyfish form. This mutated jellyfish then becomes a parasite, infecting every other creature in its vicinity into black-eyed jelliens.

9 I Was A Teenage Gary

After Squidward accidentally injects him with snail plasma, SpongeBob slowly beings morphing into a snail-sponge hybrid in a clear homage to the 80s Cronenberg body horror classic The Fly. The new hybrid SpongeSnail's body functions slow down, and he loses the ability to talk. The only line that he can say is, "something is wrong with meeoowww!"

Squidward turns frantic after seeing his neighbor's grotesque transformation. Scared by SpongeBob's pleas for help, the tentacled neighbor starts running around in his house. Amidst the ruckus, the plasma syringe accidentally pierces his nose, turning him into a snail, too. Unlike other scary SpongeBob episodes, the story ends on an unresolved cliffhanger, as Gary and the snail versions of Squidward and SpongeBob meowing under the moon.

8 Spongehenge

Though not exactly creepy, the season five episode "Songehenge" definitely has an eerie and off-kilter feel to it. Harsh winds are causing SpongeBob's pores to whistle a tune that attracts jellyfish, and he becomes a societal outcast as a result. Forced to take refuge in a cave, he constructs giant stone monuments of himself in an effort to draw the attention of the jellyfish away from him.

His plan is eventually successful, but, in a hilarious parody of Planet of the Apes, SpongeBob returns to discover that he's now in the far future and the Krusty Krab has been destroyed.

7 Graveyard Shift

The crew at Krusty Krabs are forced to work overtime one night. Bored with the night shift and with the restaurant empty, Squidward conjures up a spooky tale to creep out SpongeBob. His story is pretty detailed as he talks about the "Hash-Slinging Slasher," a former fry cook whose clumsiness lost him a hand, which was later replaced with a spatula. He later got run over by a bus and was "fired from his job" at his funeral.

The atmospheric horror builds up as a figure eerily similar to the Slasher makes its appearance, equally scaring Squidward and SpongeBob. While the end is anti-climatic, it's one of the best creepy episodes of the show, even featuring an appearance by Count Orlok from Nosferatu.

6 Ghoul Fools

Ghoul Fools brings back a ghostly pirate character named The Flying Dutchman along with his nemesis, Lord Poltergeist. The latter scares SpongeBob and Patrick with imagery and jump scares that might be a bit too edgy for the casual tones of the series. There are brains with eyeballs being served in balls, snakes slithering inside SpongeBob, screaming doorknobs, and the like.

The ending is surreal and unsettling, too, as The Flying Dutchman transforms into a nuclear bomb of sorts and explodes over Lord Poltergeist, while a mushroom cloud forms. The rest of the Bikini Bottom is then shown to be existing in some form of the afterlife, as all the characters sport green outlines around them like the titular ghouls. It's unusually morbid for the typically happy-go-lucky Nickelodeon show.

5 SquidBob TentaclePants

Squidward is easily the most tragic character of the series. An experiment with Sandy's machine ends up Squidward and SpongeBob fusing together in one body. SpongeBob sees this as a good opportunity to stay friends forever, while Squidward, on the other hand, is desperate to get out of this mess, as he has a clarinet recital.

In the end, even after getting separated, Squidward's talent fails to amuse audiences. In a fit of rage, he ends up fiddling with the machine yet again. The scene ends on a very depressing note as Squidward tells his therapist that "it all started when I was born." The full shot reveals that he has been fused in a ball of flesh, with other characters like Sandy and Mr. Krabs. This scene was cut in some European reruns for being too gruesome.

4 Rock Bottom

Perhaps one of the most memorable installments of SpongeBob SquarePants ever to air on television, "Rock Bottom" sees SpongeBob and Patrick mistakenly disembark at the wrong bus stop, landing them in the inescapable and utterly alien titular town.

Though Patrick eventually catches a bus back to Bikini Bottom, SpongeBob is forced to wait for a while, though the Rock Bottom transit authority seems weirdly keen on preventing him from returning home. The episode is evocative of being a stranger in an unfamiliar, hostile place, a deep-seated fear of nearly every child.

3 Krabby Patty Creature Feature

This is yet another episode that features body horror. When his customers being craving a new dish, Mr. Krabs forces Sandy and SpongeBob to create a new kind of Krabby Patty. But, something about this new Patty starts turning the customers into "Krabby Patty Creatures."

The transformation is quite scary for a normal SpongeBob episode, as all the characters find their insides bursting and transform into a literal patty. Everyone from the titular character's friends to children on the street mutates into such abominations. Some, like in the aforementioned episode, even fuse together. Eventually, Bikini Bottom turns into a nightmarish apocalypse.

2 Are You Happy Now?

Squidward gets fed up with the everyday monotony and mediocrity of his life. Spongebob struggles to make happy memories for his friend, taking him to a violin concert and an art gallery. The plans end up making him more depressed, and the bow of a violinist strikes his eye, a scene skipped in the Bahasa Indonesian version for being too violent.

Squidward tries giving up on life quite literally as he stays locked inside his home for two weeks. In a particularly gruesome scene, he seems prepared to do something that certainly wouldn't be allowed on daytime television, though it's eventually played off as a bit of unusually bleak humor.

1 SB-129

Easily one of the series' most recognizable early episodes, SB-129 sees Squidward transported thousands of years into the future only to discover that SpongeBob and Patrick are as omnipresent in his life as they always were.

After traveling to the distant past and discovering much of the same, Squidward accidentally breaks his time machine, transporting him to some sort of blank void, which sends him into a panic. This episode explores themes of nihilism and existential dread, which are incredibly heavy topics for young children to be exposed to.

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