The annual Halloween special for The Simpsons is broken into three stories:

1. Dial "M" For Murder - Bart and Lisa decide to enact revenge on each others' teachers in a classic Hitchcock criss cross maneuver so know one will detect the other.  Unfortunately Bart takes his too far when he murders Lisa's teacher and soon Lisa realizes she either needs to take Mrs. K's life or Bart's...
2. Don't Have a Cow, Mankind - When Krusty the Klown introduces a new burger squared that reeks of mad cow disease, it turns the town into a pack of zombies.  When the Simpson family discovers Bart is the cure, they must make it to a safe zone with Apu's help
3. The Musical - When Homer accidentally slips in Moe's he lands on the beer distillery, Moe tells Marge that Homer left and attempts to seduce her.  He feeds her beer laces with Homer's blood and she slowly falls for him.