The Rex Montana Story - S1-E35
Revealing mistake: When Flint follows the Indians, there's a strong wind blowing. But the two puffy clouds in the backdrop sky never move.
Revealing mistake: Diamond's office building has an automated push-button elevator (quite a rarity in the 1950s). But when he and Hastings exit and walk into the hall, the elevator doors remain open long after they should have closed. There's also no break in the floor where the steel plating for the lift car ought to be, making it all the more obvious that it's a studio mock-up rather than a real elevator. (00:01:20)
The Case of the Wayward Wife - S3-E13
Revealing mistake: Perry and Della step into an elevator but there is no line in the floor between the floor they are on and the elevator floor. It's continuous.