Revealing mistake: Watch the opening sequence of this episode very carefully - Clarkson, May and Hammond are not in Downing Street (they are on a set that stands on the BBC backlot) and library footage of the Prime Minister is cleverly edited in to make it look as if they were there at the same time. Even taking into account the fact that the Prime Minister's security service would never allow such an intrusion onto Downing Street, the line up of the shots does not quite match - our three intrepid heroes should be visible in shot when the Prime Minister is shown exiting number 10, but they are nowhere to be seen. It is all sleight of hand and clever editing, but detectable if you watch carefully enough.
Mr. Monk Meets Dale the Whale - S1-E4
Revealing mistake: When Monk is showing how Dale and his Doctor murdered the judge one can see that the knitting of the right chair is already cut to ensure that the policeman will fall through it when he later steps on it.
Revealing mistake: There are numerous shots where "Avid"s ginger hair can be seen coming out of the masks.
Revealing mistake: While Horatio and Alexx are examining the prostitute's body, you can see the corpse breath in a side view.
Revealing mistake: As Bunk is ordering ballistics to rush comparisons, the dead bodyguard is breathing during the scene. (00:01:55)
Forever Red - S1-E34
Revealing mistake: When TJ "Shift's into Turbo" He misses the morpher with his key. The key goes behind his arm.
Revealing mistake: Right after the scene with the witches, Cindy disguises herself while offering coffee to the producer Corky Shimatzu. However, besides the Groucho Marx glasses and nose, she is wearing her normal outfit when a few minutes earlier, she was wearing her witch outfit, had green makeup on her face, and her hair was a completely different style. Then a few minutes later, she goes back to her play costume. That makeup must have taken at least an hour and would take just as long to remove it. Yet she changes from and back to it in a matter of minutes.
Revealing mistake: The left pinball in the arcade (which later disappears) has the body of a "Star Trek TNG" machine - but the backglass is purely fictional. (00:17:45)
Revealing mistake: At the end of the episode, when they are eating the sausages Kel made, when the phone rings pause the DVD. The phone cord is plugged into the wall, yet the power switch is off.
The Big 'I Have a Dream' Episode - S1-E20
Revealing mistake: After Mona has the second dream she rushes into the living room, and when she pulls the blanket off Spencer she is shocked that he's completely naked, but we can see the actor is actually clothed when he gets up to get dressed. (00:10:55)
Volleybrawl - S3-E17
Revealing mistake: The same shot of Ceri's team missing the ball and the oposing team winning the point is used several times. You can tell it's the same shot by the way a certain character jumps.
Revealing mistake: The list of intelligence agents names that Johnny Marks steals is a list of the same names repeated over and over again.
Revealing mistake: Air Force Colonel Owen Crawford and his two personal assistants are poring over classified intelligence files in the Colonel's office. When they start to review a slideshow of photographs, one assistant sets up a projector screen and turns off the office lights as the other assistant switches on the slide projector. Photographic images immediately appear on the screen in the background, but the first assistant is still standing directly in front of the slide projector in the foreground. Not only does he not eclipse the projected image on the screen, but no projected image appears on the assistant's body. Obviously, the images on the screen in the background are projected from another source far off-camera. (00:48:50)