Bart is seen walking around a dark room with paintings and tries to introduce the show, but Marge and Maggie interrupt telling Bart to tell the viewers that the stories are scary and that they might prefer to listen to the old „The War of the Worlds“ broadcast on the radio instead. Bart hushes them away and starts telling the story of the first painting.
Homer finds out that Carl and Lenny have already eaten all of the donuts. He yells out that he'd sell his soul for a donut, and in that second, the Devil (who is Ned Flanders) appears and offers to give him one in exchange for his soul.
Homer signs the contract and receives the promised donut. But before he finishes it, he realizes that as long as he doesn't finish it, the contract is unfulfilled. The Devil (Flanders) swears Homer will go to Hell sooner or later before disappearing.
During the night, homer gets hungry and eats the last bits of the donut, the devil immediately comes in to take homer to hell just as the rest of the family rushes in. Lisa demands a fair process and the devil agrees to hold the process the next day but until then, Homer has to spend the night and day in hell.
In hell homer is tortured in several ways, such as being cut into pieces and being fed more donuts than the human body can consume, of course, as its homer simpson we‘re talking about, he has no problem eating all the donuts in question which leaves the demon feeding him baffled.
The process is held the next day at midnight, just as it seems that they lost, they discover a paper in which homer promises marge his soul which legally makes marge Simpson the rightful owner of homer‘s soul. So the (very pissed off) devil has to leave homer on earth. As revenge, the devil curses homer with having a donut for a head for all eternity.
The segment starts off with bart and milhouse in the school bus on their way to school as the bus suddenly looses control. It ends up being nothing more than a nightmare as bart wakes up terrified. When Bart walks into the school bus he sees skinner who explains that he has to drive with the bus since his mother took his car keys as punishment for him calling a woman.
Bart sits next to milhouse as he looks out the window and spots a small creature on the side of the bus. He immediately tells milhouse to take a look who doesnt dare since he fears getting kicked in the butt if he bends over to look. Bart sees the gremling digging into the bus and pulling out cables. He calls out to everyone and explains the situation but when they go to look, nothing‘s there. Everyone returns to their seats but bart still sees the creature and is absolutely terrified.
Skinner eventually walks up to bart and closes the blinds so he stops complaining. Bart secretly reopens the blinds and screams in terror as he sees housekeeper willie right infront of the window. He begs milhouse to believe him who out of fear decides to sit away from bart. Bart sees the creature messing with the wheel and yells out for the busdriver to stop the bus. Skinner tackles him down and willie ties him to his seat.
Bart then befriends the swiss exchange students who looses his ties, bart takes the chance and opens the window to attack the creature with fire. He succeeds but still nobody believes him even as they see the damaged school bus. Bart is placed into an asylum. While he is being driven off, he sees the creature in the window holding flanders‘ head up to him.
Then it cuts over to Bart back at the museum showing us the last painting of the day which features dogs playing Poker.
We then see the simpsons family watch the news in which its reported that a mysterious creature (which according to the hints is obviously a vampire) has killed a human. The police believes it to be a mummy but lisa gets up from the couch screaming about it being a vampire. Homer laughs and reassures her that vampires are in fact not real.
Then the news report that mr. Burns has bought up the blood-bank of springfield.
We then see the family driving to a dinner with mr. Burns in his private house in pensylvania. We then see them entering the house as mr. Burns seems to be a obvious vampire. They eat dinner and Lisa excuses herself (and bart right with her) to go to the bathroom. They wander through the house and find mr. burns‘ secret vampire room. Theyre then chased by undead vampires, Bart falls right into their hands and mr. Burns stings bart because of which bart turns into a vampire.
The family then goes home and go to sleep while bart sneaks out and stings a bunch of other kids (they also turn to vampires) and wakes up lisa while knocking at her window and flying right outside of it. He then breaks the window and goes to bite lisa as their parents (and maggie) come rushing in to stop him. Bart laughs and flies away as a Bat.
Lisa declares that the only way to get Bart back into who he was, was to kill mr. Burns (the main vampire a.k.a the cause for all this). The family then goes back to Burns‘ house and the family find the secret vampire room again. They find Burns‘ coffin and Homer digs a dagger right through his heart.
Everything is back to normal, except for Grandpa, who turns out to be a vampire, well atleast so it seems until Lisa screams up in fear and asks how this is possible if burns is dead. Marge then reveals that she was the main vampire all along.
They then turn to the camera, wish the audience a happy Halloween and then start singing some type of christmas carol lol.
Maybe the second segment could technically be canon if Bart was released before the next episode took place but because skinner said something about bart spending his life in the asylum it seems unlikely.
None of them appear to be canon to be honest with you. Homer doesnt have a donut for a head, Bart isn‘t in any asylum and the family arent vampires.
Connection to Gravity falls:
You could say that Homer making a deal with the devil is similar to Bill making a deal with his victims but personally i think that would be a bit of a reach😭