Revealing mistake: When Charlie and Jake are at the supermarket Jake tells his uncle to switch milk brands, and when Charlie puts the Dairy Farm 1/2 gallon milk carton back on the shelf it wobbles easily back and forth, revealing it's actually an empty carton.
Continuity mistake: When Alan first meets Rose, she eventually says "He (Charlie) has a very musky scent" with her head turning to look at Alan. When the camera cuts to Alan, he says "uh huh" and Rose is all of a sudden looking straight ahead. (00:10:40)
Continuity mistake: While Evelyn is at Charlie's asking Alan if he's considered that there may be another man at Judith's "shacking up with her," Evelyn is wearing a blue 2-piece skirt suit, but in Charlie's close-up Evelyn's wearing a white suit with a red floral pattern when she's standing in front of Charlie, at the left side of the screen. (In the original pilot Evelyn is played by Blythe Danner wearing the floral suit, but she had to back out and was replaced by Holland Taylor, who's wearing the blue suit).
Continuity mistake: While Alan's sitting on the couch, Evelyn's talking to Alan "helping...through a very difficult time," and in the shots facing Alan all of the books on the table behind him, and also the books on the couch's side table keep changing - not just their position, all the books actually become different books. Additionally, in the shots facing Charlie, the books beside the chair and the books/CDs/DVDs on the bookcase change as well.
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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