Last Exit to Springfield - S4-E17
Continuity mistake: When Mr Burns is telling Homer to resign, he has glasses on in the first shot in the scene. However his glasses are on his desk the next shot onwards.
Last Exit to Springfield - S4-E17
Continuity mistake: When the dentist shows Ralph the Big Book of British Smiles, he first shows him a picture of Sherlock Holmes with horrid teeth and all of his teeth are there. When Ralph starts getting terrified of it, it shows the same picture, but this time one of his teeth on the bottom right hand corner of his mouth is missing.
So It Has Come to This: The Simpsons Clip Show - S4-E18
Audio problem: When Lisa explains the origin of April Fools Day, we hear Homer, Marge, Bart and Lisa chanting "Blood For Baal." But, we see that Lisa is not taking part in the ritual and her mouth isn't moving. (00:02:15)
So It Has Come to This: The Simpsons Clip Show - S4-E18
Audio problem: After Homer puts the old milk in the fridge and Bart takes a drink from it you will then see Marge use a fork to take the milk out of the carton. Marge says "woof" but her mouth does not move in sequence with the audio.
Continuity mistake: During the Itchy and Scratchy episode at the beginning, Itchy's hammer changes from being held above him to beside him between shots.
Continuity mistake: When Roger Meyers throws his nameplate at the writer the second time, the animation is repeated from when he threw it at him earlier. It's more obvious because his mouth doesn't match what he's saying and the background is orange instead of purple like the rest of the scene.
Continuity mistake: Millhouse is in the classroom at the beginning when Principal Skinner says that superintendent Chalmers is coming for a surprise inspection, but when they show Nelson he is getting crud put down his shirt. How could he be at two places at once?
Continuity mistake: On 'Whacking Day,' Homer is seen charging people to park on his lawn. But later when the snakes are lured to the Simpson house, there are no cars there.
Continuity mistake: When the bottle of bourbon is found and taken out of Marge's pocket, the bottle is grey. But when Sanjay throws it to Apu, and Apu catches it, the bottle has now changed to a brown colour. (00:08:30)
Continuity mistake: When Marge comes to pay for her shopping, she empties her left pocket on her coat, but when Sanjay finds it in her pocket, it's in her left pocket. We know it wasn't in her pocket anyway because when Sanjay finds it, it is bigger than the size of her pocket.
Audio problem: At the end of the episode the statue of Jimmy Carter with Marge's hairdo is unveiled, and the assembled throng applaud her reaction. They are all chattering away, but no sound is coming out of their mouths - we only hear the sound of clapping.
Krusty Gets Kancelled - S4-E22
Other mistake: When the Red Hot Chili Peppers are performing on Krusty's TV special, bassist Flea is playing a standard electric guitar.
Krusty Gets Kancelled - S4-E22
Continuity mistake: When Bart and Lisa are helping Bette Midler pick up trash on the highway, Bette picks up an empty can which says Buzz Cola on it. Just as she yells, "You pigs!" the label on the can switches to Duff Beer.
Homer's Barbershop Quartet - S5-E1
Continuity mistake: Skinner puts the helmet on his head and we see Hermann from inside the helmet, and he has no cigarette in his mouth. When we see the shot from outside, he does. (00:03:10)
Homer's Barbershop Quartet - S5-E1
Continuity mistake: When Bart and Lisa find the record Melvin and the Squirrels, they hand it to the Comic Book Guy to play. While the record is in his hand you can still see it displayed on the rack. (00:03:40)
Homer's Barbershop Quartet - S5-E1
Continuity mistake: The wording "Be Sharps" changes size on the album when the family is laughing at Bart. It gets much smaller. (00:04:00)
Homer's Barbershop Quartet - S5-E1
Continuity mistake: When you see a shot of the church from outside in the scene where the bee sharps sing there, look closely at the sign. It says 'Also: The Bee Sharps', only they don't name themselves that until later on in that episode. (00:05:40)
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.