About this Simpsons episode:
The Simpsons - Treehouse of Horror XXI is the 4th episode of season 22 and number 468 overall in the series. It is also part of the Halloween special series.
While carving pumpkins, Bart takes a knife and etches a smile into Homer's pants. Homer responds by choking Bart, and Bart puts a flaming pumpkin on Homer's head. Professor Frink then welcomes the audience and warns them of the content of the show, presenting a TiVo remote control to fast forward through the scary stuff. But after accidentally fast forwarding to the end of the special, and exposing spoilers, a shameful Frink uses the remote on himself and fast forwards his life until he is turned to a pile of dust. The Frankenstein's Monster who was created by Frink makes a reference to The Office, and remembers his days working at "Monster Mifflin" with the Mummy, the Wolf Man, a zombie and a witch.

"War and Pieces"
Marge, worried about the effects of excessively violent video games, encourages Bart and Milhouse to try playing some of the classic board games in the attic. After rejecting the "lame" ones, they discover an old board game called "Satan's Path." Upon playing it, all the rejected games come to life turning the town into a giant game board. Lisa reads the instructions, which are in Latin, and says the two must beat all the games to finish Satan's Path and restore everything to normal. Milhouse dies during the game of Battleship, but Bart manages to finish it, returning everything back to normal (even bringing Milhouse back to life). Bart and Milhouse state that they just play hangman but the game brings the hangman to life. With only one more letter remaining (WHEEL _F F_RTUNE), Milhouse guesses the number 3, which results in Bart and Milhouse being hanged.

"Master and Cadaver"
When Homer and Marge set sail on a romantic second honeymoon, their time together is interrupted when they rescue a castaway. Introducing himself as Roger, the castaway explains that he was a chef on a yacht called the Albatross, and was knocked out after attempting to stop a poisoning on his ship. Roger decides to make them a pie, but Homer becomes convinced that Roger poisoned the guests on the Albatross. He grabs the pie from Marge and throws it out the window. Marge chastises Homer, but looks out a window and sees a dead shark with the pie pan in its mouth. Homer and Marge take matters into their own hands as they seemingly kill Roger using a metal pole, and knock his body overboard. However, finding the Albatross, they realize Roger was telling the truth and that some of the passengers are still alive, as one of the people administered an antidote. Roger appears and explains that the shark they saw had died from a fuel leakage from Homer and Marge's boat. Homer then kills Roger, the surviving Albatross crew, and a pelican, to cover their tracks. However, unable to bear the guilt, Marge eats the poisoned pie, much to Homer's horror. The story is then revealed to be Maggie's imagination while she is taking a bath. Homer asks Marge what Maggie thinks about while bathing, which she responds, "Just sugar plums and buttercups." Maggie then shadily moves her eyes, puts on a hat, and drinks milk like Alex from A Clockwork Orange.

"Tweenlight"
Lisa falls in love with a mysterious new student named Edmund. After saving Lisa from a bus, two cars, a bicycle and a Segway PT, Edmund reveals himself to be a vampire. Lisa is not frightened by this and the two spark a romance much to the dismay of Milhouse, who turns into a were-poodle. Marge invites Edmund and his father, Count Dracula, to dinner. Edmund and Lisa are both embarrassed by their fathers and decide to leave. Homer and Dracula track them down to a cathedral in "Dracula-la Land." They see Edmund climbing up a tower with Lisa, so Homer forces Dracula to carry him up. Lisa wants to become a vampire, but has second thoughts after learning that she would be eight years old forever. Edmund says that "the blood-lust is upon him" and he has to bite something. Homer stops Dracula with a cross, and is amazed to learn vampires love their kids also. Edmund and his father reconcile, and Homer saves Lisa by offering himself up in her place as the two vampires feast on him. However, they both die from the bad cholesterol in Homer's blood as he is turned into a vampire. Transforming into a bat to fly home, Homer's fat causes him to fall to his death. His body is carried off by were-poodle Milhouse while Lisa watches in dismay.