Susan Lynch (Stage) & Suranne Jones (Claire) also worked together on The Secret of Crickley Hall (2012) as Lili Peel & Eve Caleigh respectively.
Lennie James (Nelly) and Stephen Graham (Melon) previously worked together on Snatch (2000) as Sol & Tommy respectively.
Nadine Marshall (DS O'Halloran) & Rob Jarvis (Daniel) also worked together on episode 5.4 Shadows in the Sky (2015) of Vera (2011) as Ellie Thorne & Mick Mckittrick respectively.