Wild Barts Can't Be Broken - S10-E11
Continuity mistake: When Wendell is among the kids seen inside the police van, his skin is a lot less pale than usual.
Revealing mistake: When Fat Tony says,"I am not so much disappointed as I am blinded with rage", the dark circles under his eyes disappear for a split second.
Continuity mistake: A huge fight begins in front of Mark Hamill's stage. Homer, Quimby, Hamill, Bart and Lisa escape the fight through an emergency exit right behind the people fighting. But in a shot of the five running out, the people fighting inside have disappeared.
Revealing mistake: When Homer says "Oh, baby we got him now" whilst arriving in the airport, you can see half of Doctor Hibbert's face in the background, but you can see he doesn't have any eyebrows or eyes.
Continuity mistake: When Homer has the Bill Of Rights, he ends up ripping several parts of it. The rips keep alternating between shots. (00:05:25)
Other mistake: When Marge takes Homer back inside, his car is seen blocking the traffic. But at least one side of the traffic is driving on the wrong side of the road. The drivers behind Homer's car are on the right side of the road. And the drivers behind Homer's car from the opposite direction are driving on the left side but facing the drivers behind Homer's car on the other side. Either way, one half of the traffic are driving on the wrong side of the road. (00:02:35)
Other mistake: When Homer returns home, Marge says his car is blocking the traffic. But there is some space on the road where his car isn't. The traffic could easily have driven through the empty space. (00:02:30)
The Wizard of Evergreen Terrace - S10-E2
Continuity mistake: During the very last scene Homer is sitting on the sofa next to Bart watching the news. But in the last shot he's sitting in a separate chair next to the sofa.
Thirty Minutes Over Tokyo - S10-E23
Continuity mistake: When Lisa gets the tickets on the "volcano", she is a few inches away from the end of the bridge. When it falls and Marge runs onto the bridge, she is now in the middle of it.
Thirty Minutes Over Tokyo - S10-E23
Audio problem: In America Town, when Bart says "These prices suck. 10,000 Yen for coleslaw?", his mouth doesn't match what he is saying.
Continuity mistake: When Homer and Ned attempt to escape from their Vegas wives at the buffet. The Vegas Wives are directly in front of them, when Homer runs off he runs in an opposite direction, nowhere near them. When Homer runs out, the Vegas wives are right next to him.
Continuity mistake: While in the cafeteria, Principal Skinner asks Milhouse to lower his eyebrows. Behind him, there is a bulletin board that changes from brown to purple.
Continuity mistake: While Lisa is standing in front of the table with her friends in the cafeteria, we see that the trays appear during the first shot, then after the camera zooms in on Lisa's table, the trays disappear. Then during the third shot, Lisa calls Alex over to her table. Look at the table again: the trays have reappeared. (00:06:00)
Continuity mistake: When Lisa is getting the answers to her test, the coffee mug changes colors.
Other mistake: When Nelson puts the intestine into the model's mouth, the size of the gut should not increase. It is the same amount of stuff going in a cycle, so where does all the stuff come from? (00:03:15)
Other mistake: The amount of gunk that come from Bart's model at the start is not proportionate to the size of the model. In other words, there couldn't be enough gunk to cover the entire inside of the bus.
Revealing mistake: When Nelson is offering Lisa the fraction quiz answers, right before Lisa says she's never cheated before and won't again, her right hand disappears for a single frame.
Other mistake: After Bart complains that Jonathan Harris isn't Dr. Smith, Harris says for Bart to meet him in the food court. Then the Robot says "Danger Bart Simpson, danger." How did he know Bart's name?
Simpsons Bible Stories - S10-E18
Plot hole: Somehow, despite being enslaved and being nowhere near anything that could help them, the Jews have a camel, which we did not see coming across the channel.
Revealing mistake: There are two Ruth Powers in the same shot, when the people are crowding on Homer at the mall.
Answer: I'm not sure if this is the one you're thinking of, but an episode of "Ray Bradbury Theatre," called "A Sound of Thunder," dealt with a similar matter: a group of hunters travel back in time to hunt dinosaurs, only to find things have changed when they get back because someone stepped on a butterfly.
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