In the eighth annual "Treehouse of Horror" episode, Homer discovers he is the last man left alive after a neutron bomb destroys Springfield in the segment "The HΩmega Man". In "Fly vs. Fly", Homer buys a transporter that Bart uses to switch bodies with a housefly, and "Easy-Bake Coven'" features Marge being accused of witchcraft in a Puritan rendition of 1649 Springfield. The episode was written by Mike Scully, David S. Cohen and Ned Goldreyer, and was directed by Mark Kirkland.
A Fox censor simply named Fox Censor, sitting at his desk reading through the script and deleting things, proudly announces that thanks to his editing tonight's Simpsons episode is rated TV-G. But as he says this, a hand with a sword appears out of the on-screen rating icon and stabs him in the back repeatedly. Every time he gets stabbed, the rating gets higher. In the end, the rating is "TV-666" and Censor collapses dead onto the desk. Blood pours down the front to reveal the title, "The Simpsons Halloween Special VIII."
Mayor Quimby generates a great deal of controversy over a "frog's legs" joke he makes about France and he refuses to apologize. Lisa becomes worried that France will launch an attack against them. Homer tries to reassure her by saying that they have a bomb shelter, but it turns out to be a cardboard box in the backyard. So, Homer goes to Herman's Military Antiques to look for a real bomb shelter. He is looking at the Withstand-inator when the French president launches a neutron bomb directly into Springfield. Homer, completely unharmed, emerges from the shelter and complains to Herman's corpse about the food. On the way home, Homer doesn't take notice to the lifeless town. At a green traffic light, he becomes annoyed because the person in front of him won't go. He gets out of his car and decides to handle things with a "little friendly punching". He punches the driver in the head, mistaking their head turning into dust for a sign that he 'still has it'. He then notices a newspaper headline that tells about the bomb that blew up Springfield, and he seems to be the only person to have survived. He misses his family, but he quickly gets over his loss and realizes he can do anything he wants. Homer takes this opportunity to dance naked in the church, when he is confronted by a band of Springfield citizens including Moe, Ned Flanders, Mr. Burns, Dr. Hibbert, Sideshow Mel, Chief Wiggum, Lenny, Carl, Otto, Principal Skinner, Willie, Apu, Smithers, Barney, Duffman, Lionel Hutz, Professor Frink, Cletus and the Sea Captain; who have become mutants, but they prefer to be called 'freaks' or 'monsters'. They claim that they want to create a perfect world in which the mistakes of the past will be eliminated. This, of course, includes killing Homer. Homer flees in his car back home with the freaks chasing him in a type of zombie car. Upon arriving home, Homer is greeted by his family, who survived the blast because their house was protected by so many layers of lead paint. Seeing Homer reunited with his family, the freaks see the error of their ways. Ned Flanders hopes they can build a Utopian society where freaks and norms can live together in peace. Marge seems to agree at first, but she and the children open fire with shotguns that they were hiding behind their backs, killing all of the freaks. Homer and his family decide to take advantage of the nuclear holocaust and go and steal some Ferrari's.
Homer buys a teleporter from Professor Frink at his yard sale. Bart asks if he can use it but, Homer refuses. That night, Bart tries to sneak Snowball II into the teleporter. However, Santa's Little Helper jumps in at the same time. As the pets come out, Santa's Little Helper and Snowball II have been merged into two creatures. Suddenly, the fly lands on Bart's arm and this brings him to a great idea. To become a fly superhero, he grabs the fly and steps into the teleporter. Unfortunately, it doesn't work very good. Bart comes out his normal head, but with the body of the fly and meanwhile the fly has his body. The rest of the family wakes up and sees Bart's body with a fly's head. They decide that it must be Bart and accept him as their family, although its non-human behavior. Meanwhile, Bart regrets his decision and tries to tell his family what happened. Unfortunately, they can't hear him and the fly-boy that likes its new life, almost kills him. That night, Bart uses Lisa's sax to tell her what happened. Suddenly, the fly-boy jumps on Lisa from the ceiling. Scared Lisa runs to the kitchen where the fly-boy starts strangling her. Bart wants to help, only to be caught and eaten by the fly-boy. Angry Lisa then knocks him into the teleporter and Bart appears in the living room normal. Homer then grabs an ax and obviously is about to destroy the teleporter, but then turns to Bart and starts chasing him around for using the teleporter.
The year is 1649 and the town of Sprynge-Fielde is witness to many witch burnings. Later in the church, the townspeople try to figure out whom to condemn next. People start accusing others and soon they erupt into chaos, until Marge intervenes. She tries to talk sense into the townspeople, but Moe accuses her of being a witch. Mayor Quimby assures her that she is entitled to due process which means she will be thrown off a cliff with a broomstick. If she is a witch she will be able to fly to safety, in which case the authorities expect her to report back for punishment. If she is not a witch, then she will fall to an honorable Christian death.
Lisa tries to speak on her mother's behalf, but to no avail and Marge gets shoved off the cliff by Wiggum's henchmen. As Reverend Lovejoy speaks to the mob about having done the Lord's work, they hear a cackle and all look up, stunned to see that a green-skinned Marge is flying on the broomstick, as she really is a witch and an evil one, who vows to conquer the town. She returns to her elder sisters Patty and Selma in their mountain lair close to Sprynge-Fielde. The sisters watch Ned Flanders and Maude Flanders talking about how the witches may eat their children, thus giving them the idea in the first place. The three set off for Sprynge-Fielde on their broomsticks. They knock on the Flanders' door and demand the kids. They put the kids in sacks and are about to leave, when Maude offers the witches gingerbread men instead. The witches like these better than the kids and let Rod & Todd go. They go to each house, getting goodies in exchange for not eating kids. Marge remarks that she wishes they hadn't eaten so many children before they got to the Flanders' house. As they fly off, the Sea Captain says that is how the tradition of Halloween started, with Maude Flanders' quick thinking leading to the Halloween we know today, and that "it was the story of the first Caramel Cod, I mean, Halloween.
The next year, the whole town is celebrating Halloween. Homer eggs the door of a house from which no candy was received. Lisa points out that it is their house. When everybody starts laughing at him, he accuses Lisa of being a witch, prompting the townspeople to start chasing her down the street.
"The HΩmega Man" was written by Mike Scully, "Fly Vs. Fly" was written by David S. Cohen and "Easy-Bake Coven" was written by Ned Goldreyer. Large portions of the "Fly vs. Fly" segment were cut, including the original ending where the fly also emerges from the teleporter, but is considerably larger and the Simpson family ride it to the mall.
The producers had trouble with the censors over several segments in this episode. The opening segment of the episode, which features Fox Censor the censor being stabbed to death and was pitched by David Mirkin, had a difficult time getting through the real life censors. They had issues with the size of the knife and the sound effects used. Originally Fox was stabbed with a dagger, but the censors found it too gruesome, but found the use of a sword acceptable, so it was used instead. The censors also had issues with Homer dancing naked on the altar in the church, so it was changed so that he was just dancing on the floor.
This episode was the only Treehouse of Horror episode that was directed by Mark Kirkland. It was also the last episode that was worked on by Brad Bird, who left the show to direct The Iron Giant. "Easy-Bake Coven" was storyboarded by Kirkland and the backgrounds were designed by Lance Wilder. Although Kang and Kodos make brief appearances in every Treehouse of Horror episode, their brief appearance in this one was nearly cut. David X. Cohen managed to persuade the producers to leave the scene in.
The episode received positive reviews from critics and fans. The A.V. Club named Comic Book Guy's line "Oh, I've wasted my life" as one of the quotes from The Simpsons that can be used in everyday situations.
"Treehouse of Horror VIII" won a Golden Reel Award in 1998 for "Best Sound Editing - Television Animated Specials" for Robert Mackston, Travis Powers, Norm MacLeod and Terry Greene.Alf Clausen received an Emmy Award nomination for "Outstanding Music Composition for a Series (Dramatic Underscore)" for this episode, which he ultimately lost.