Revealing mistake: In this episode Dorothy and Blanche are awakened by a stench coming from the kitchen. After they go to inspect, we see that Rose is making some sort of Krispies treat. As you see her carry the plate to offer Dorothy and Blanch one, you can see that the plate is empty. And once they all start to eat them you can easily see that none of them are actually picking anything up and putting in their mouths.
Revealing mistake: Episode Aired 12th December. In the laundrette a shelf had fallen off the wall and Dot Cotton needed someone to fix it. You could see the wall was false, as every time Dot touched the shelf, the wall was wobbling. Later same episode Martin Fowler fixed the shelf he said something like "the wall will fall down before the shelf does" - very true.
Revealing mistake: When Bjornson is in Oslo he calls Catherine, who is still in Alesund, from a pay phone. But located behind him is a poster listing emergency numbers for the municipality of Giske, revealing that this scene was filmed there, just outside of Alesund.
Tooth and Consequences - S1-E41
Revealing mistake: The glue holding the mustache to actor David Birney's (Dr. Myron Mandel) upper lip is visible.
Revealing mistake: Episode 1720: When Todd is knocked down by the van, you can see that it is not Kristian Schmid but a stunt double.