Music:
- Mercy, by Duffy
- Where Is Home, by Bloc Party
- Baby Plays Around, by Elvis Costello
- The Man Comes Around, by Johnny Cash
- The Holy City, by Michael Crawford
The title refers to the song of the same name by Creedence Clearwater Revival, which Herrick (Jason Watkins) briefly sings, and to George (Russell Tovey)'s transformation.
Aidan Turner (Mitchell) & John Hollingworth (Turlow) also worked together on Poldark (2015) as Ross Poldark & Captain Henshawe respectively.
The opening scene is a flashback from 2 years previous, which would place the time-line as 2007, but playing on the radio in the background of the cafe is 'Mercy' by Duffy, which was not released until March 3rd 2008.