When Inspector Lewis is listening to his old LPs, the cover of the King Crimson album "In The Court of the Crimson King" can be seen.
Jo and Felipe are seen speaking in Tagalog, the main language of The Philippines.
Robbie states that he met his late wife the night the band played NewCastle City Hall.
Joanna Lumley (Esmé Ford) and Simon Callow (Vernon Oxe) both appeared in the same episode of Agatha Christie's Marple (The Body in the Library).
In the series Inspector Morse; Trevor Byfield played Harry Field in Who Killed Harry Field? (1991), and Simon Callow and Jane Bertish appeared as husband and wife in The Wolvercote Tongue (1987) where Callow's character was a murder victim as well as appearing in this episode of Lewis.