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Treehouse of Horror XXIX

Wikisimpsons - The Simpsons Wiki
Season 30 Episode
642 "My Way or the Highway to Heaven"
"Treehouse of Horror XXIX"
"Baby You Can't Drive My Car" 644
XXVIII "Treehouse of Horror XXVIII"
"Treehouse of Horror XXIX"
"Treehouse of Horror XXX" XXX
Treehouse of Horror Episode
For the continuing series of Halloween specials, see Treehouse of Horror series.
Donut Homer.png This episode is considered non-canon and the events featured do not relate to the series and therefore may not have actually happened/existed
Treehouse of Horror XXIX
Treehouse of Horror XXIX title card.png
Episode Information
Episode Number: 643
Production Code: XABF16
Original Airdate: October 21, 2018
Show Runner(s): Al Jean
Written By: Joel H. Cohen
Directed By: Matthew Faughnan

"Treehouse of Horror XXIX" is the 4th episode of season 30 and the 643rd episode of The Simpsons. It aired on October 21, 2018


"1. Opening sequence: Homer wins an oyster-eating contest against the mythical Cthulhu.
2. Invasion of the Pod-Y Switchers: Springfield is overrun by plant body-snatchers.
3. Multiplisa-ty: Lisa finally snaps.
4: Geriatric Park: Mr. Burns opens a retirement home with some Jurassic upgrades.


Opening sequence[edit]

At the Oyster-Eating Contest at Fogburyport, the Simpson family are taking part in it, when they discover that it's a ruse to get sacrifices to Cthulhu. As Cthulhu was about to eat Homer, he challenged him to an eating contest. However, against all odds, Cthulhu loses and asks Homer any wish. Homer wishes to eat him, and so the family does. When Homer pokes his ink sac, the Treehouse of Horror XXIX logo shows up.

Invasion of the Pod-Y Switchers[edit]

In the underwater Mapple Computer Underwater Lair, Steve Mobbs introduces his successor and the MyPhone Ultima, however his successor is actually an alien ready for an invasion.

Spores are sent from the alien's home planet, and switch the Springfielders with copies of themself, including Comic Book Guy, Marge and Wiggum. Bart and Lisa try to run away with Lou in the police car, but fail.

Lisa is brought to the alien world, which is in reality an utopian world. She is welcome by Xylem and Phloem, and finds herself in what human calls Crab Nebula. But not all is as fabulous as they make it seems, as Herb Tannenbaum gives the people phones in this world too.


After a sleepover at Milhouse's, Milhouse, Nelson and Bart find themself in a cell, suddenly freed by Penelope, the one that trapped them in it. Penelope, which is actually Lisa acting strange, in a multi-personality manner, acts weird and closes them in again after they don't ask for an encore on her performance.

Things get weirder and weirder even at the Simpson House, where Lisa covers Bart's disappearance with more weirdness, while the kids try to open the door using Milhouse's head as an aries, just before scottish Lisa appears, inviting them out to face the beast, after discovering she killed Willie with an axe.

Lisa attacks and kills Milhouse and Nelson, before Bart asks her what happened to her, to which Lisa tells the story: Bart grabbed Lisa's spelling test, changing her answers, mocking Miss Hoover and granting her a F.

Lisa has a last change and gives Bart a last chance to save himself and he redeems himself, saving himself from being killed by trash, while Milhouse was transformed into a "paper boy".

Geriatric Park[edit]

Geriatric Park redirects here. For the location, see Geriatric Park (location). For the song, see Geriatric Park (song).

Mr. Burns creates Geriatric Park, a park filled with elders rejuvenated by mixing their DNA with dinosaur DNA. He brings Springfielders to the park, showing them the new "retirement home".

At first they're all human, healthy and feeling young again, with incredible strength too, but once Homer raises the temperature after Grampa complains about the temperature being too cold, they transform into dinosaur creatures.

Visitors are killed by the elders, while the family are threatened by Grampa and Jacqueline Bouvier, but Lisa courageously confronts Grampa, and find out they all just needed to be cherished and respected. In the end the family escapes alive, though their helicopter is being flown by pterodactyl Agnes.

International airdates[edit]

Country Date Channel Note
Asia December 30, 2018 Fox Asia
Hispanic America.gif Latin America June 2, 2019 Fox Latin America



Promo videos[edit]

Season 30 Episodes
Bart's Not Dead Heartbreak Hotel My Way or the Highway to Heaven Treehouse of Horror XXIX Baby You Can't Drive My Car From Russia Without Love Werking Mom Krusty the Clown Daddicus Finch 'Tis the 30th Season Mad About the Toy The Girl on the Bus I'm Dancing as Fat as I Can The Clown Stays in the Picture 101 Mitigations I Want You (She's So Heavy) E My Sports Bart vs. Itchy & Scratchy Girl's in the Band I'm Just a Girl Who Can't Say D'oh D'oh Canada Woo-hoo Dunnit? Crystal Blue-Haired Persuasion