Honeysuckle Weeks (Mae Harmer) and Don Warrington (Commissioner Selwyn Patterson) also worked together on The Five (2016), as Laura Marshall and Ray Kenwood respectively.
Kris Marshall (DI Humphrey Goodman) and Brian Bovell (Erol Dumas) also worked together on Love Actually (2003), as Colin Frissell and Radio Watford DJ respectively.
The song the team dances to at the end of the final scene, "Tiney Winey" (by Byron Lee & the Dragonaires), is reprised in Chain Reaction (2021), when J.P. Hooper (Tobi Bakare) and Marlon Pryce (Tahj Miles) sing it into the phone to lull J.P.'s infant twins to sleep.