Siobhan Finneran (Mandy) & Karl Davies (Luke) also worked together on Happy Valley (2014) as Clare Cartwright & Daniel Crawford respectively.
Timothy Spall and Matthew Lewis both starred in the Harry Potter franchise.
On Tuesday, 4th February 2020 the BBC and Rollem Productions announced that the drama would return for a 6-episode fourth stand-alone series. Series 4 will be broadcast on BBC One in the UK and will be released as a BritBox Original on BritBox in North America. No filming or air-date for series four was announced.