Flanders' head injury gives him the power to predict doom, Bart and Lisa investigate the murders of Victorian England's most prolific prostitutes, and The Simpsons go on a "fantastic voyage" into Mr. Burns' body to save Maggie from being digested.


* ArtisticLicenseBiology: The alligators that attack Hans Moleman are drawn as resembling crocodiles, namely having the lower visible when the mouth is closed.
* BodyHorror: PlayedForLaughs, as Homer ends up [[spoiler: trapped inside Burns' body after regenerating to him normal size after he was unable to leave with the family. However, he mostly is upset over not having a ''mouth of his own to eat food'' and seems to be pleased when he and Burns dance to [[RefugeInAudacity "I've Got You Under My Skin".]])]]
* DancePartyEnding
* {{Fanservice}}: Marge in third story. Before, she wonders why her swimsuit has to be so skimpy. After, whent the white blood cells are eating her clothes she is stripped to her undergarments.
* FantasticVoyagePlot: The Simpsons [[AndNowForSomethingCompletelyDifferent tour inside Mr Burns's body]].
* GettingCrapPastTheRadar: When he first finds out Ned is destined to kill him, Homer gives him a pistol, even slapping that, prompting Ned to say "Quit whacking my barrel!"
* GroinAttack: Invoked at the end of the FantasticVoyagePlot. Homer tells Mr. Burns that it's a bad idea to defy someone who can kick his balls from the inside.
* ITasteDelicious: In the opening sequence, as the family are all being prepared to eat the Simpson family, Homer consistently eats himself with delight.
* OpiumDen: The Victorian segment excurses into an opium den operated by Moe. Mr. Burns is a customer.
* NiceJobBreakingItHero: Ned's attempts to avoid killing Homer and preventing him from destroying Springfield are what ultimately lead those events to happen.
* PoorCommunicationKills: Ned's pleas for Homer to not destroy Springfield.
-->'''Ned:''' Homer, do not press the core destruct button!
-->'''Transmitted into the booth:''' Homer, (Static) press (Static) Destruct button!
-->'''Homer:''' Okay.
-->'''Ned:''' Don't do it! You'll kill everyone!
-->'''Transmitted:''' (Static) Do it! (Static) Kill everyone!
* ProfaneLastWords: There is a button in the nuclear power plant that can blow up the entire city. Ned Flanders shoots Homer to stop him from pressing the button but Homer ends up dying next to the button...only for his tongue to end up pressing it.
-->'''Ned''': Oh, you stupid, son of a-\\
''(city explodes)''
* SewerGator: How Moleman gets killed.
* ShoutOut: The opening sequence, ''Keepin' It Kodos'', is this to many sitcoms of the [[TheEighties 1980s]], and the opening song (and closing credits) is the ''Series/PerfectStrangers'' theme song.
** When the "Treehouse of Horror XV" title screen comes up, the "XV" is hammered into the steel plate by Kodos, a la the Mark VII Limited logo.
* TakeThat: To Rosie O'Donnell. When Ned Flanders predicted her new musical would close after three performances, he commented he didn't need his power to see that.
* TheDeterminator: Homer persistently tries to press the nuclear destruct button, even as he is being shot.
* TooDumbToLive: Granted most people wouldn't listen to a man talking about seeing the future. However it is taken UpToEleven when Homer doesn't even pause for thought when he thinks Ned is telling him to press the core destruct button. Not even when Ned tells him, even through the static interferance that it will kill everyone.