The Simpsons (1989)

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Audio problem: When Lisa is turned into a snail in the Bart's zombie story, she says "awww" but her mouth doesn't open.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Deliberate mistake: In "Clown Without Pity", when the Krusty doll accidentally knocks the head off of Lisa's Malibu Stacy (her doll), Krusty puts it back on but you don't see a crack where the head came off.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Continuity mistake: When Homer is escorting his family out of the house to escape the Zombies, he leaves the door wide open, but in the very next shot it is shut.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Deliberate mistake: In "Dial Z For Zombies", Homer is shooting zombies with the shotgun at the school. When he shoots the first two he just shoots them twice. Every other zombie he shoots requires him to slide the gun. It doesn't when he shoots the first couple of zombies.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Audio problem: In King Homer, after Burns and the guards on the island rush through the doors, you hear Burns say "Shoot him in the groin and belly!" But his mouth doesn't move.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Plot hole: At the theatre in the "King Homer" bit, the audience are treated to a traditional showgirl spectacle. But the girls have no curtain behind them, and so the audience should have seen Homer the ape, but they act completely surprised a minute later when Homer comes on.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Audio problem: In "Clown Without Pity" when Homer yells "The doll is trying to kill me, and the toaster's been laughing at me!" his mouth doesn't move.

Tree House of Horror III: The Simpson's Halloween Special III - S4-E5

Audio problem: In "Clown Without Pity" when Homer is singing in the bath, his mouth doesn't match what he is singing. (00:05:20)