Zoe Wanamaker co-starred in the long running UK sitcom My Family. One episode was devoted to a disagreement between Wanamaker and a friend / rival as to the best TV cop series. The friend favoured Frost (David Jason), the more sophisticated Wanamaker was adamant that nothing came close to Inspector Morse.
When Morse and Lewis enter the PAX house, Lewis says "dib dib dib, sir". This is actually "dyb dyb dyb", which was a chant formerly used by the Scouts, from the initials of one of their sayings, "Do Your Best".
In this episode there is a scene where actress Zoe Wanamaker is talking while standing in front of a poster for the play Ariadne. Years later she went on to play the character Ariadne Oliver in Agatha Christie's "Poirot".
Outside a pub with Lewis, Morse quotes from the works of the Persian poet Omar Khayyam (1048-1133) in the translation by Edward Fitzgerald (1859), quatrain 22: "For some we loved, the loveliest and the best".