Continuity mistake: Alan is sitting at the kitchen table talking to his son Jake about a math test on which Jake got a bad grade. At the beginning of the scene Alan holds the open test in his left hand. When the camera switches back to him a second later the test is now in his right hand. Finally at the end of the scene the test is back in his left hand but is now folded. (00:04:50)
Continuity mistake: When Jake is looking at the Oshikuru magazine his grip changes from the bottom to the side. (00:04:15)
Revealing mistake: When Alan is wrestling on the floor with the naked lady you can hear her voice perfectly clearly despite her mouth being covered with a towel and being face down. (00:02:15)
Revealing mistake: When Charlie is shaving at the start, he's not actually touching the skin with the razor. (00:00:05)
Chosen answer: Alan might have thought the bra was too fancy to belong to a regular woman, "I'd love to meet the girl who filled this", he says. He assumed it was one of Charlie's many women.
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