During the filming of Colin Dexter's cameo role as a tramp, filmed from the top of the Carfax tower, a real down-and-out approached him, grabbed his bottle of "meths" and ran off - only to find that it contained just water.
On the panel game show Episode #4.1 (2010), Martin Clunes claimed (not as part of the game) he intentionally addressed Morse as "Cheese Inspector" instead of "Chief Inspector". At one point he says something that could be "Cheeve Inspector", but nothing clearer is in the episode. He also claimed he has done similar pranks on other shows, sometimes at the request of friends.
The final freeze frame close up of Morse changing from colour to black and white echoes the closing frames of Sweeney! and Sweeney 2; both starring John Thaw as Jack Regan
Not for the first time, Morse's Jag is missing its rear view mirror in the final scene - it having been present throughout the rest of the episode
Anna Massey [Lady Emily Balcombe] would have a part in the pilot episode of Inspector Lewis as a different character.