Blood, Devastation, Death, War and Horror - S3-E4
Visible crew/equipment: When the Merchant Banker sends Mr. Ford through the trap door, you can see a crew member waiting to catch him below the stage. (00:06:50)
Factual error: When the allies are testing their joke on the private in the field, just before he starts laughing at it, a bright red car drives past behind him. You can see it in a break in the trees. This sketch is set in WW2, and the car is obviously not from that era.
Visible crew/equipment: Just after Florence Nightingale gets knocked out, a crew member can be seen behind Michael Palin for a short time.
Suggested correction: The scene is set in an active television studio filming a sinister quiz show. The crew member visible is one of the crew of the fictional television show.
Scott of the Antarctic - S2-E10
Revealing mistake: In the last shot, the familiar 16 tons weight is broken at the top, showing that it is in fact not a solid weight, but a hollow box.