The Simpsons Halloween Special: Tree House of Horror - S2-E3
Continuity mistake: In the Raven scene, you can see Homer's drool on his jacket, but in the next shot and following shots it's gone.
Continuity mistake: When Homer is talking to the makers of Police Cops, the person on the far left's hair changes from brown to grey instantly between shots.
Continuity mistake: When Homer lights his albums on fire, he watches Weird Al doing a parody of his song. When it's over, the fire is gone and there are no ashes where it would be.
Continuity mistake: When Flanders' wife gives them the sandwiches in the recreation room there are 12 sandwiches, when Homer asks Ned to get him a beer there are only 6.
Treehouse of Horror XIII - S14-E1
Continuity mistake: The people standing to the left of the rock, as the Comic Book Guy (as a faun) walks onto it, changes. In the first shot the police officers and Raplh stand there, in the second shot it's a panda. (00:19:25)
Treehouse of Horror XIII - S14-E1
Continuity mistake: When Homer starts to strangle his clone, the clone throws the boxes it was carrying, to the floor. In a following shot the boxes have vanished. (00:04:20)
Sleeping with the Enemy - S16-E3
Continuity mistake: When Lisa is making the game right at the beginning, we see her put a line at the bottom of her one, yet when the shot changes, it is gone. (00:00:25)
Treehouse of Horror XV - S16-E1
Continuity mistake: When Chief Wiggum is running for the hot air balloon, you can see in the distance no one is in it, yet when he arrives Professor Frink is in it. (00:13:50)
The President Wore Pearls - S15-E3
Continuity mistake: When Lisa goes into Principle Skinner's office to resign, there is a mug and some papers on the desk. When she wants to use the microphone, the desk is clear.
Tree House of Horror XII - S13-E1
Continuity mistake: In the end title sequence, the frogman thing vomits and leaves a stain on the parking lot. When Pierce Brosnan drives away in his car, there is no stain. (00:21:05)
Continuity mistake: In the Meat video Jimmy's steak is first seen to be a little thin. In the closeup it's very thick, then thin again in the next shot.
Continuity mistake: When Maggie's dummy is spinning after the goat has taken her, the ground is clear. In the next close up shot there are tufts of grass and clumps of dirt there.
The Two Mrs. Nahasapeemapetilons - S9-E7
Continuity mistake: When we see the garden and Bart throwing Hymns into the fire the large tree is fully green. After the shot of Bart,the camera goes up and we see branches with no leaves on them though.
Tree House of Horror X - S11-E4
Continuity mistake: When Marge hits Ned Flanders, she pulls over, in the middle of the road. But When they go to see who they've hit, and when Homer picks Ned up and 'talks' to him, the car has disappeared from the road.
Tree House of Horror V - S6-E6
Continuity mistake: When the Simpsons shed their skin at the end, the skin falls to the floor. In the next shot it's gone.
Tree House of Horror V - S6-E6
Continuity mistake: In the third story, the five remaining students are all in one classroom - Bart, Lisa, Milhouse, Wendell, and Ralph. Ralph disappears when the other four try to escape.
Continuity mistake: At The Town hall meeting Mayor Quimby's microphone is first seen to be plain grey. In the following shot it has dark lines on it.
Itchy and Scratchy: The Movie - S4-E6
Continuity mistake: When Bart and Lisa are watching TV, Bart says something like 'I've got my ticket' and pats a ticket that is inside his shirt pocket (which there is none). But later in that same scene when they are still watching TV, both the pocket and the ticket have gone. (00:12:20 - 00:14:15)
Continuity mistake: The old men beside Grandpa when Homer plows the retirement home switch places, depending on whether it's a long or a close shot. (00:10:00)
Continuity mistake: As Homer is giving his speech to the dressed up monkeys, all of the monkeys are dressed in blue suits and you can also see there is one monkey next to the stairs on the stage. In the next shot of Homer leaving the stage there is now six monkeys, with only one wearing a suit and it is grey. (00:19:45)
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.