- Author Existence Failure:
- Willie Rushton, one of the four regulars on the show since the 1970s, passed away in December 1996 due to complications from heart surgery. Since then, his spot has been filled by a guest for each episode.
- Humphrey Lyttleton sadly passed away in early 2008. The show was very nearly cancelled afterwards until they went with a series of guest hosts, then settled with Jack Dee as host.
- Regular panelist and Sixth Ranger Jeremy Hardy, who became known as the unofficial fourth member (almost always joining them on tour) sadly passed away in 2019 from cancer.
- Tim Brooke-Taylor passed away from the Coronavirus in 2020. Barry and Graeme were already more or less in semi-retirement at this point, appearing at just two out of six episodes per series, leaving the show's whole future after the epidemic unclear.
- Defictionalization: Mornington Nomic is an attempt to construct an actual, playable version of "Mornington Crescent".
- Fan Nickname: A common way of identifying episodes is by naming them after the final game, which is almost always Late Arrivals or some variation such as Film Club.
- Flip-Flop of God: There have been several different explanations for how they came up with Mornington Crescent. Humph once claimed that the panellists invented it in order to annoy a producer they disliked, former producer Geoffrey Perkins has been credited with it, whilst Barry Cryer said it was not an original idea to the show and it had been around since the sixties.
- Keep Circulating the Tapes:
- Owing to the nature of the programme's CD releases (each release contains four compilations rather than whole episodes), the only episodes that are commercially available in their entirety are the two Christmas specials. Some attempt seems to be made at rectifying this with the new "Live" range, which does release uncut recordings.
- In a case of literal Keep Circulating the Tapes, whole episodes (but still without Pick-Up Song) were released on audio tape in the '90s.
- No Budget:
- Mentioned in a round of "Word For Word". Paul Merton buzzed Barry and Graeme, and Humph initially overruled his challenge, saying that they only had one buzzer and that was with Tim and Paul. He then says "...oh, thank you, Paul" as footsteps are heard, and then Graeme says "For those of you listening in stereo — it's over here now!" Later, when Barry challenges Tim and Paul, Paul says "we'd better have the buzzer back then, hadn't we?" and footsteps are heard again.
- There's also a round called No Budget, where the panellists have to think up "cut-price" version of well-known media, such as Wuthering Hillocks or The Chihuahua of the Baskervilles.
- Recast as a Regular:
- Humphrey was initially a rotating chairman with Barry Cryer, he took over sole duties in the second series whilst Barry became a team member.
- After serving as a rotating host with Humph in series one,note Barry Cryer replaced Bill Oddie as Graeme's teammate from series two onwards.
- After being a guest host when Humph passed away, Jack Dee was eventually made the full-time host in 2009.
- Recycled Script: There are several cases of identical versions of One Songs to the Tune of Another appearing several years apart (Barry Cryer sang the Bob the Builder theme to the tune of "The Girl from Ipanema" in episodes from 2005 and 2016, and Marcus Brigstocke and John Finnemore sang "Common People" to the tune of "If You're Happy and You Know It" in 2011 and 2018), the same songs being used for Pick-Up Song and Swanee-Kazoo, and Sound Charades being reused word-for-word.
- Screwed by the Lawyers: The "Pick-Up Song" round was excluded from any of the CD releases due to the cost of licensing the recordings for a long time. It finally appeared for the first time on the second Live release, and has since made its way into some of the compilation releases.
- Throw It In!:
- Humph would occasionally misread something, and the improvisation by the panellists in response to this would usually be thrown in.
- In another episode, Jack misread "Tobacconist's Film Club" as "Tobogganist's Film Club", before Graeme pointed out his mistake. The round turned into a mix of smoking puns and winter sports puns.
- The sound once dropped significantly in the middle of a joke. Jack asked "Did the sound just drop then, on that?", and got answers of "Yes" from the panel and some of the audience.Jack: Oh good. I like to make sure, because otherwise Barry thinks he's having a stroke.Barry: I wish...
- What Could Have Been: Due to Humph's unfortunate death, the regular trio of Graeme, Barry and Tim were unsure if they wanted to continue, as were the producers. They eventually agreed to return for a series of guest hosts, then signed on again when Jack Dee was chosen as host over Stephen Fry and Rob Brydon.
Trivia / I'm Sorry I Haven't a Clue