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Treehouse of Horror XXX

Wikisimpsons - The Simpsons Wiki
Season 31 Episode
665 "The Fat Blue Line"
"Treehouse of Horror XXX"
"Gorillas on the Mast" 667
XXIX "Treehouse of Horror XXIX"
"Treehouse of Horror XXX"
"Treehouse of Horror XXXI" XXXI
Treehouse of Horror Episode

Donut Homer.png This THOH is considered non-canon and the events featured do not relate to the series and therefore may not have actually happened/existed.

The reason behind this decision is: The episode is part of the Treehouse of Horror series.

If you dispute this, please bring it up on the episode's talk page.

This article is about the episode. For other uses of "Treehouse of Horror XXX", see Treehouse of Horror XXX (disambiguation).
"Treehouse of Horror XXX"
Treehouse of Horror XXX promo 1.png
Episode Information
Episode number: 666
Season number: S31 E4
Production code: YABF18
Original airdate: October 20, 2019
Showrunner: Al Jean
Written by: J. Stewart Burns
Directed by: Timothy Bailey

"Treehouse of Horror XXX" is the fourth episode of season 31 of The Simpsons and the six-hundred and sixty-sixth episode overall. It is also the thirtieth installment in the Treehouse of Horror series and consists of three parts. It originally aired on October 20, 2019. The episode was written by J. Stewart Burns and directed by Timothy Bailey.


"1. Opening sequence: a demon Maggie.
2. Danger Things: a mission to rescue Milhouse from another dimension.
3. Heaven Swipes Right: dead-Homer's spirit trying on some new bodies for size.
4. When Hairy Met Slimy: Selma finally finding love in an unlikely place - the alien in the basement.


Opening sequence[edit]

It's Halloween, and Marge is having a new baby born, when from her womb comes out an unexpected boy. Homer is terrified of the prospective of a second Bart (who is completing text on a wall with graffiti to say "boner", so he asks Dr. Hibbert to change the baby, to which Hibbert gives them Maggie, but warns him "she tested positive for evil".

Maggie demonstrates her powers by choking Hibbert and then placing him in the baby incubator and having it going up all the way to 1,800 °F incinerating him. They take her home and she makes the toys' head turn and twist till all the fluff inside breaks out, burns the posters Homer places on the wall and eats and spits a bird in his face. Homer begins to ponder if it was the right decision.

At her birthday, she burns Gerald's unibrow and makes Kearney, Shauna and Dolph hang themselves from the window. Ned decides it's time to stop this, especially after she changes Rod and Todd to be bad boys, saying he'll perform three funerals that night.

At the cathedral, Ned is stopped by Marge, but he warns them she's bearing the mark of the beast, Mickey Mouse, before switching to the correct one, the number of the Beast, 666. Having not being killed, she destroys the ceiling of the cathedral and impales Homer, Marge, and Ned.

Danger Things[edit]

In the '80s, in Bart's treehouse, Bart is playing E.T., with Martin, Milhouse and Nelson. After getting a game over, the kids split up to go back home on their bikes, when Milhouse gets attacked.

Luann and Kirk get worried as Milhouse hasn't come back at home, and Kirk starts breaking the wall trying to find him. The police find his bike near the woods, while Kirk places letters on the wall to see if he's in another dimension and he can communicate with them.

Since Milhouse is gone, Luann confesses she's having an affair, and Disco Stu comes down the stairs revealing it's him. Milhouse sends an SOS with the letters but due to the problems they're having they send him and his lights up to his room.

At the Simpsons home, Lisa gets a call from Milhouse, but once she says she doesn't like him in a romantic way, he hangs up. Lisa goes to the Starcourt Mall, which sign gets invaded by rats to become the Ratscourt Mall. The kids are playing at the arcade and she informs them of Milhouse being trapped in the other dimension, and he calls for them from the video game Bart was playing.

They go to Professor Frink's lab to find a way in, and Lisa uses a sensory deprivation tank to find Milhouse. In the Over Under, Lisa finds Milhouse, but they're spotted by the Demogorgons that bite his left leg off when he doesn't stop talking.

They try to escape the Domegorgons in town, while other monsters devastate the city. Lisa reveals she has psychic powers but they're trapped until Homer saves them with a flame thrower, saying that Mr. Burns opened the portal to find monsters for a secret government project. Homer informs them they're all trapped in the dimension so they sit down on the couch before finding out there's a Ned version of the Demogorgon, so Homer burns him.

Heaven Swipes Right[edit]

At the Springfield Atoms Stadium, Homer, Moe, Lenny and Carl are watching the Springfield Atoms vs. Shelbyville Shelbyvillians match, and when the crowd starts shouting choke, a hotdog ends up choking Homer to death.

Arriving in Heaven, he meets St. Greeter, who welcomes him with the pun on his name, but Homer doesn't forgive the pun so he gets damned to Hell. Homer finds out God sold Heaven to Google, before discovering he died before his time, but can't be sent back to Earth in his body due to the decay.

Homer is given the option to live the life of a man who was going to die that day, so Homer chooses the Atoms' quarterback Case Diggs. He goes to Marge and she loves the new body, but he ruins it in one night by overeating. Bart and Marge convince him to try Superintendent Chalmers as the next body.

At school, Homer makes Skinner give Bart all As and twist his nipple till its deep purple, and then goes to his house just to see he makes very little money, so Homer changes his body again, but Marge has had enough. Homer has to settle in for one body and stop changing, so he chooses the one of the man that loves her as much as he does, Moe, however Moe finds himself in Maggie's body and informs her he's thirsty.

When Hairy Met Slimy[edit]

At the Power Plant, Selma enters a maximum security door to sneak a smoke. She finds herself in a laboratory, where she meets Kang and they fall in love. After offering to provide the secret to clean, natural energy Mr. Burns wants to dissect him, so they flee, to go to a distant galaxy, with Homer's much-obliged help.

Selma and Homer sneak Kang out in a waste container full of rats, but Burns finds them. Kang bites off Smithers' head and knocks out Burns, with Barney driving the trio out in his car. Mr. Burns and the military follow, but his driver is shot as they flee to Mt. Springfield. Thinking they're safe, Kodos arrives with a ship but a shooting takes place and Selma is hit in the stomach.

Kang then pulls out Thanos' infinity gauntlet to eliminate all military people, and when Burns survives, he hits him with a tin can. Kang then heals Selma and tells her he's pregnant.

Patty arrives, protesting they're too different, being of different zodiac signs, but Kang points out he's from Sagittarius. Patty begs her not to go but falls in love with Kodos. They fly to space, and find themselves on the honeymoon planet, in the cool season, where it's 4,000 °F.



Dennis Perkins of The A.V. Club gave the episode a B- rating, saying that the episode "doesn't have many particularly inventive or straight-up clever laughs along the way".[1]

As of September 2020, the episode has a 6.9 rating on IBDb[2] and a 7.5 rating on TV.com.[3]

International airdates[edit]

Country Date Channel Note
Asia January 5, 2020 Fox Asia [4]



Promo videos[edit]

The Saga of Carl - title screen.png Wikisimpsons has a collection of images related to "Treehouse of Horror XXX".
Season 31 Episodes
The Winter of Our Monetized Content Go Big or Go Homer The Fat Blue Line Treehouse of Horror XXX Gorillas on the Mast Marge the Lumberjill Livin La Pura Vida Thanksgiving of Horror Todd, Todd, Why Hast Thou Forsaken Me? Bobby, It's Cold Outside Hail to the Teeth The Miseducation of Lisa Simpson Frinkcoin Bart the Bad Guy Screenless Better Off Ned Highway to Well The Incredible Lightness of Being a Baby Warrin' Priests: Part One Warrin' Priests: Part Two The Hateful Eight-Year-Olds The Way of the Dog