Revealing mistake: Most of the time, whenever the characters have a hot drink there is nothing in the cup.
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.
My Doctor has a Cow Puppet - S1-E22
Revealing mistake: When Rose scares Charlie, he bangs into the wall and the entire wall moves.
The Price of Healthy Gums Is Eternal Vigilance - S2-E6
Revealing mistake: When Alan is banging on the bathroom door, the entire set is shaking.
Frankenstein and the Horny Villagers - S2-E8
Revealing mistake: Alan slams his bedroom door shut when Judith has turned up. When he does the wall wobbles. (00:06:50)
Revealing mistake: When Charlie is shaving at the start, he's not actually touching the skin with the razor. (00:00:05)
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)
Last Chance to See Those Tattoos - S2-E11
Revealing mistake: Charlie is typing away on his computer. But he is tapping the same 3 keys. (00:09:45)
Can You Eat Human Flesh With Wooden Teeth? - S2-E16
Revealing mistake: When driving back after leaving Jake in the rain, the rain that settles on the bonnet of the car starts to pool. On a moving car this doesn't happen. Therefore you can tell the car wasn't moving. (00:09:20)
Does This Smell Funny to You? - S2-E24
Revealing mistake: At the start, Jake is writing the end of his report in class. However, watch closely and his pencil isn't on the paper. (00:00:25)
Weekend in Bangkok with Two Olympic Gymnasts - S3-E1
Revealing mistake: When Alan falls off the ladder you can see the ladder has been set up so it will fall back safely. As the ladder goes back towards the balcony rail, it hits the railing and bounces up. The bottom of the ladder, which is unseen, seems to be planted as it does not move during this. When Alan was climbing up and down the ladder, it wasn't secured with anything at the bottom. Thus the reason for him falling off the ladder. (00:03:35)
Your Dismissive Attitude Toward Boobs - S3-E4
Revealing mistake: When Alan picks up his big suitcase it's clear by the way he handles it that it's empty. (00:17:05)
Revealing mistake: At the very end, as Evelyn is leaving she gets her coat stuck in the door frame. However the coat doesn't move, indicating that Evelyn is stood outside the door waiting for the shot to be over. (00:22:00)
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.
Help Daddy Find His Toenail - S5-E6
Revealing mistake: When Charlie reads the paper after the banquet the text is all the same, just repeated. (00:16:20)
Help Daddy Find His Toenail - S5-E6
Revealing mistake: When Judith slams her door the wall wobbles. (00:17:30)
Shoes, Hats, Pickle Jar Lids - S5-E9
Revealing mistake: When Charlie is in the Ferrari, his gets a call from Teddy. When Charlie brings the iPhone to his ear and talks to Teddy, you can see that the iPhone is upside down showing that no one actually called his phone.
Ixnay on the Oggie Day - S7-E18
Revealing mistake: Charlie turns the money he's holding toward the camera, making it too obvious that it's prop money and not real.
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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