The Mook, the Chef, the Wife, and Her Homer - S18-E1
Continuity mistake: Just as Otto is about to put in the grand funk tape you can briefly see an different tape in the recorder. Slow motion is not needed but a sharp eye is.
The Mook, the Chef, the Wife, and Her Homer - S18-E1
Continuity mistake: When Bart and Fat Tony's accomplices are going to meet Krusty, Krusty's nose can briefly be seen as white when it should be red.
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The Mook, the Chef, the Wife, and Her Homer - S18-E1
Revealing mistake: When Fat Tony says "The Calabresis. My archenemies in waste management." while driving the carpool, a huge line briefly appears around his cheek and mouth.
The Mook, the Chef, the Wife, and Her Homer - S18-E1
Continuity mistake: When Lisa grabs Ottos tape recorder her necklace is orange but when she gets off the bus it is white.
Answer: Willy referred to an encounter he believed he had with actual aliens, while Wiggum thought he was referring to the arcade game.