- Actor Allusion: When Abigail Thaw's character first meets Morse she wonders if they've met before. When Morse says no she says 'In another life maybe'.
- The Danza: Strange was given the first name 'James', in tribute to James Grout, who played the character in Inspector Morse
- Directed by Cast Member: Shaun Evans directs the second episode of series six, Apollo.
- Edited for Syndication: Over 10 minutes per episode is cut to fit the program in the 90-minute Masterpiece time slot (and shoehorn in the rather pointless introduction by Alan Cumming) on PBS in the United States. This can make some episodes confusing to American viewers. (Thankfully, unlike the early seasons of Lewis, the full uncut episodes are released on disc and on Amazon Prime.)
- Hey, It's That Place!:
- Horsted Keynes Station (restored to 1930s Southern Railway appearance, and consequently painted green) stands in for Oxford Station (which, in the 1960s, would have been painted Western Region brown).
- The railway sequences in "Passenger" were filmed at the Mid-Hants Railway, which again means everything's green rather than brown.
- I Meant to Do That: Meta example. According to creator/writer Russell Lewis, any anachronisms you may spot in the show have been deliberately put there for the benefit of those viewers of a mind to look out for them.
- You Look Familiar: The series has so far taken the same attitude toward casting as Lewis, meaning that while guest actors aren't re-used as different characters in this series, actors who've previously appeared in Inspector Morse or Lewis can be brought back in different parts to what they originally played.
- Notably, "Rocket" has guest appearances by Martin Jarvis (who appeared in Morse) and Jenny Seagrove (who appeared in Lewis).
- For that matter, Roger Allam had previously played Denis Cornford in the Morse episode "Death Is Now My Neighbour".
- James Wilby, who appears in "Neverland", also stars in the Lewis episode "Expiation".
- Lucy Boynton, one of the students in "Nocturne", portrayed a child prodigy in "The Gift of Promise" (Lewis).
- Danny Webb, who portrayed the corrupt DS Arthur Lott in the pilot, also starred in the pilot episode of Lewis ("Reputation") as Tom Pollock.
- Patrick Malahide appeared in "Driven to Distraction" (Morse) and the pilot of Endeavour.
- Beyond the Creator Cameo appearances by Colin Dexter, three actors to date have appeared in all three programs:
- Richard Durden played Alan Richards in "The Dead of Jericho" (Morse), John Gracey in "The Soul of Genius" (Lewis), and Prof. Alexander Richmond in "Quartet" (Endeavour).
- Andrew Paul was a criminal suspect accused of an arson attack on a bookshop in "Deceived by Flight" (Morse), Ron Tibbitt in "Intelligent Design" (Lewis), and Joe Dozier in "Quartet" (Endeavour).
- Glen Davies portrayed a policeman in "Twilight of the Gods" (Morse), a workman in "Intelligent Design" (Lewis), and Burt Talbot in "Lazaretto" (Endeavour).
- In addition, opera singer Janis Kelly's voice has been heard in two episodes of Inspector Morse (including as the singing voice of Nicole Burgess in "Death of the Self"), four episodes of Lewis, and the pilot of Endeavour.
Trivia / Endeavour