You'll be trembling helpless lumps of fear when we are done
Grim unearthly creatures flaunting nauseating features make for ghastly midnight screechers,
You'll be speechless but for AAAAAAAAAHH!!!
It's Halloween night, and Patrick helps SpongeBob overcome his fear of the holiday by convincing him that "scary equals funny". SpongeBob ends up having a laugh riot on Halloween night, which attracts the attention of the Flying Dutchman. Finding the scares provided in Bikini Bottom lackluster, the Dutchman decides to show SpongeBob and Patrick how truly frightening Halloween can be.
"The Legend of Boo-Kini Bottom" contains examples of:
- Art Shift: This is the second special to use stop-motion animation for the characters, while certain effects also utilize puppetry. Within the episode itself, the inside of SpongeBob's mind is animated in a psychedelic style reminiscent of Yellow Submarine.
- Berserk Button: The Flying Dutchman hates it when anyone dares laugh at Halloween.
- Call-Back: Plankton warns the Flying Dutchman that he's personally seen some frightening things in SpongeBob's brain. Plankton's referring to when he entered SpongeBob's mind in The SpongeBob Movie: Sponge Out of Water and found the Sugar Bowl lying inside his brain.
- Continuity Nod: SpongeBob wears his flower costume from "Krabby Land" for Halloween.
- Delayed Reaction: When the Flying Dutchman scares a trick or treater, it takes a few seconds for him to react before screaming in terror.
- Embarrassing Old Photo: When thinking of how to scare the Flying Dutchman while he's trapped inside his mind, SpongeBob notes that he really gets scared when his mother shows people his naked baby pictures, which gives him the idea to scare the Flying Dutchman by thinking up himself as a giant naked infant.
- Evil Is Not a Toy: After SpongeBob flees the Dutchman's ship, Plankton's soul escapes from his cage and tries to convince the Dutchman to partner with him to take over the world, ruling it 70-30. The Dutchman uses his powers to transform Plankton into his minion.
- Faux Horrific: Patrick thinks Squidward scaring trick-or-treaters away with onions is truly terrifying.
- Fog of Doom: The Flying Dutchman unleashes a green fog that steals the souls of SpongeBob's friends.
- Halloween Episode: This is the second episode of the show to revolve around Halloween, the first being "Scaredy Pants" back in season one. Both episodes feature SpongeBob trying to get over his fears of the holiday, and have the Flying Dutchman in a prominent role.
- Haunted House: Mr. Krabs and Plankton turn the Krusty Krab and Chum Bucket into haunted houses based off the other's restaurant.
- Horrifying the Horror: The Flying Dutchman is terrified by the overly saccharine images he sees within SpongeBob's psyche.
- Indecipherable Lyrics: One criticism about The Scare Song is that the large amount of background noise in the scene make it almost impossible to hear the song's lyrics.
- Kids Are Cruel: After seeing the Flying Dutchman steal the souls of Squidward and Mr. Krabs right in front of them, a couple of kids proceed to egg both their unconscious bodies and the Krusty Krab.
- Metaphorgotten: When Patrick tries to help SpongeBob get over his fear of Halloween.Patrick: SpongeBob, don't you know the old saying? "The only thing you have to fear is...yourself!"
- Oh, Crap!: SpongeBob brushes off seeing the imprisoned souls of his friends, assuming they're just more illusions made by the Flying Dutchman. It's only once he sees Patrick's soul imprisoned and his lifeless body beside him that he begins to freak out.
- Shout-Out: "Krabby Patties are people! They're people patties! You're eating people patties!"
- The animated segment inside SpongeBob's brain is reminiscent of Yellow Submarine.
- The Something Song: The Scare Song.
- Special Edition Title: The stop motion opening from "Truth or Square" is used, though it's played with the show's regular theme song rather than the remixed version by Cee-Lo Green.
- We Can Rule Together: Plankton attempts to do this with the Flying Dutchman by saying when he takes over the world, they split it 70-30. The Dutchman is not impressed and turns Plankton into an Igor-like servant.
- Wingding Eyes: When the Dutchman finally admits to being scared of what's inside SpongeBob's brain, his pupils turn into tombstones.