In the pilot, the character Dorothea Frazil, played by Abigail Thaw, on her first meeting with the young Morse says, "Haven't we met before?" He shakes his head and says no. As he walks away, she gazes warmly at him "...maybe in another life..." She's referring to her personal daughter-father relationship with the older Morse, John Thaw.
Musical Morse: The inspector's last name, translated into Morse Code, reads as " - - / - - - / . - . / . . . / . " Impressively, this code is precisely reflected in theme music written by Barrington Pheloung, and is easily identified at the end of S1 Episode 2 (Fugue). In the final scene, as E. Morse looks on the sunset over the quad, bells begin to chime. Next, violins can be heard beginning a loop of the musical version of letters M.O.R.S.E., playing on a frequency of 329.63 Hz (tonal E in music). Soon, a masterful orchestration is woven in, diversifying this subtle nod to cryptography. Considering the content of the episode, this thematic and compositional brilliance is perfectly placed.
Writer of the original Inspector Morse novels, Colin Dexter, made cameo appearances in the first three series of this show as well as the previous shows: Inspecteur Morse (1987) and Inspecteur Lewis (2006). He continues to make "appearances" even after his retirement and subsequent death in 2017: appearing on the set as a photograph, a caricature, a sculpture, a written reference to his name, etc.
All episodes in the first six series have one-word titles. One word from each series is a musical term. In order, they are: Fugue, Nocturne, Coda, Canticle, Quartet, and Deguello. (The last is the most obscure; it is the name of a bugle call used by the Mexican army.)
Colin Dexter decided to write his first detective novel whilst on holiday in Wales. He decided to name the character after his close friend and 'the cleverest man he had ever met', Sir Jeremy Morse, the Chairman of Lloyds Bank. Initially, he never gave Morse a first name but, in an episode when the character is in hospital, the name E. Morse is on the bottom of the bed. After being pushed to give him a name, Colin Dexter and his wife looked up the names of the people who sailed to America on the "Mayflower" and found that there was one Endeavour Jones. They also liked it as it was the name of Captain Cook's ship.