Camping In - S1-E4
Other mistake: The episode takes place on March 2nd, 1973 (date of the newspaper shown by Mr. Mash), but in Mr. Rumbold's office the sale chart for the month of March is already fully filled up.

Starring: Frank Thornton, John Inman, Mollie Sugden, Wendy Richard
Genres: Comedy
Camping In - S1-E4
Other mistake: The episode takes place on March 2nd, 1973 (date of the newspaper shown by Mr. Mash), but in Mr. Rumbold's office the sale chart for the month of March is already fully filled up.
Continuity mistake: The Gentlemen's and Ladies' Department is on the first, third, or fourth floor of Grace Brothers, depending on the episode.
Mr. Humphries: I'm free!
Trivia: Frank Thornton, Mollie Sugden, John Inman, Wendy Richard and Nicholas Smith are the only actors to appear in all 69 episodes of the show.
Question: If Mrs. Slocombe had squatters in her new flat, why didn't she simply call the police and have them removed?
Answer: That wasn't possible in 1972. Until recently squatting was a civil offence in the UK, not a criminal one, and removing squatters was a complex and time consuming business.