The Foggiest Notion (2) - S3-E12
Factual error: The British curator from whom Lord Ffogg steals a collection of artifacts needs to go back to school (or someone in Batman's prop dept. does). While most of the signs are correctly spelled and punctuated ("Duchess of Desborough's Diamonds," "Her Majesty's Priceless Snuffboxes," etc.), the one marked "Lady Easterlands Jeweled Easter Eggs" is missing its requisite possessive apostrophe. (The closed captioner noticed, though, and corrected the mistake there). (00:11:15)
Answer: There wasn't one singular city used. It was shot in and around various locations in California, plus on a lot of sets and backlots. Ex. Some scenes were shot in LA, some in Pasadena, some in Santa Barbara, etc.
TedStixon