Come In, Your Time Is Up - S8-E4
Revealing mistake: In the very first scene Captain Mainwaring and Sergeant Wilson cast multiple shadows despite supposedly being in bright sunshine.
Revealing mistake: When Stemple and Jason argue on the porch, an electric light bulb is very apparent in the lantern beside the door. (00:41:00)
Revealing mistake: Halfway through the show, the officers get a flat. As Malloy is getting ready to jack up the car, Reed starts using the lug nut wrench to loosen up the nuts. He repeatedly turns the wrench clockwise, which would tighten the nuts.
Revealing mistake: The painted backdrop depicting the street and distant buildings is much too close to the Mayberry City Council office. As people come and go, they cast shadows on the backdrop.