Rough Night in Hump Junction (aka His Ugly Bundle) - S5-E15
Continuity mistake: When Charlie is with Mia and her father comes in, she's saying: "Daddy, this is Charlie, remember I told you about him." Back when Mia and Charlie were dating, he actually met Mia's parents at least twice.
Bad News from the Clinic - S2-E5
Continuity mistake: After Charlie steals Jake's fries and asks him to squirt some ketchup on them, the bottle moves around the table between angles.
Continuity mistake: When anyone goes to Alan's room in Charlie's house, they always exit/enter from the left of the room entrance (when they exit the go left and up the hall then make another left). This doesn't match the floor plan of the beach house though, as the living room has been shown to be more straight out of the room.
I'd Like to Start with the Cat - S6-E15
Continuity mistake: When Chelsea and Charlie are in the coffee shop talking about how they're doing, Charlie is drinking a cappuccino-type drink with caramel or some type of syrup or drizzle on the inside of the glass. Once Charlie says something along the lines of "She's a real ball buster, I can't get away with anything", the camera cuts back and forth between Charlie and Chelsea and with each cut, the amount of caramel on the inside of the glass increases and decreases.
818-jklpuzo - S7-E1
Continuity mistake: Charlie tells the psychiatrist that apart from being constipated everything is fine and the house is paid off. However later on when Walden moves in, it is said there are three mortgages on the house which Alan can't afford (which is why Walden moves in in the first place).
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.
I Found Your Moustache - S7-E17
Character mistake: Charlie mentions Alan's 1989 Volvo. Actually it is a 2nd generation Volvo V70, built between 2000 and 2007.
Dead from the Waist Down - S8-E11
Factual error: Alan and Lyndsey are playing scrabble. Alan is shown laying tiles down horizontally, and claims that he is using the "Z" on a triple letter score, and the "I" on a double word score, changing "it" to "ziti". This is impossible on a normal Scrabble board - those multiplier squares are all offset from each other except one row, and then they're five squares apart.
I Merely Slept With a Commie - S4-E17
Continuity mistake: When Charlie is talking to his mum after meeting her new people, Evelyn's hand constantly changes position.
A Live Woman of Proven Fertility - S4-E5
Revealing mistake: When driving back from dropping Herb off at Judith's, there is a purple tinge to Alan's face from projecting the background.
A Sympathetic Crotch to Cry On - S2-E21
Character mistake: Jake is shown playing on a Nintendo DS throughout the episode. He calls it a GameBoy when he talks about it.
Kinda Like Necrophilia - S5-E10
Continuity mistake: As Alan runs away screaming about betrayal, Berta begins to pour Charlie a cup of coffee. Charlie's first two or three fingers are hooked through the handle of the cup. The shot changes and Berta is still pouring but now Charlie's index finger is alongside the rim of the cup.
Continuity mistake: What Isabella is doing with her hands at the start keeps changing. (00:02:10)
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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