Audio problem: At the start of the film we see the twins flipping burgers in their restaurant. We see that while one is throwing the burgers the other is catching them in the buns, and then dusting them with a metal jar of something. After every burger he bangs the jar on the table a few times. One one occasion, he actually bangs the jar on a burger bun, yet the sound effect is still played.
Continuity mistake: When Bob and Walt walk by the harbour it is snowing heavily, then in the next shot it almost seems to have stopped snowing. (00:12:50)
Factual error: It is impossible for Walt and Bob Tenor to be conjoined twins because they aren't identical. The condition only occurs when a zygote (fertilised egg) doesn't split completely during meiosis (cell division) to form identical twins.
Visible crew/equipment: When Bob and Walt are being wheeled out of the hospital after the separation, just when the doors are opening in the reflection of the blue on the left, you can see the entire camera crew move along as well as the camera. When the camera disappears, another crew member can be seen running back.
Continuity mistake: We see that the join between Bob and Walt is very flexible, and can be twisted and contorted easily. Why is it then that when the brothers are lying in bed and Bob turns on his side to sleep, does Walt move with him. They should in fact be facing away from each other.
Factual error: First of all, Walt & Bob couldn't be conjoined twins. Conjoined twins have to be identical. While not all identical twins look 100% alike, they still have some similarities. Bob & Walt look nothing alike. Second of all, conjoined twins attached at the liver are the easiest to separate. The liver regenerates, so even if one was left with less, it would still grow back to the correct size. They could've been easily separated.
Continuity mistake: When Bob takes May to talk in private, after she returns, April is holding a bottle of beer. When the scene cuts to them walking down the pool, April can be seen in the background with no bottle. (01:23:40)
Continuity mistake: When they're talking about the operation in the diner, the coffee mug in front of Walt is pointing to the left of the screen. In a later shot it is pointing almost directly toward the camera. (01:16:05)
Factual error: The Tenor boys say they are from Martha's Vineyard. But all the New England outside shots are actually Rockport, Mass.
Continuity mistake: When May comes back to talk to Bob, the torch behind her is not lit. When it cuts to a different angle the torch is lit. (01:23:20)
Chosen answer: Greg Kinnear is singing himself - DVD commentary.
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