A notable number of the ensemble cast in this series happen to have previously featured in "Doctor Who", namely Anjli Mohindra, Lu Corfield, Adjoa Andoh, Mark Lewis Jones & Connor Calland.
This is the atleast the third time Anjli Mohindra has starred in a television series as a Police Officer - namely Wild Bill, The Suspect and most recently this, The Red King.
Maeve Courtier-Lilley (Winter Bain) and Lloyd Meredith (Eric Crowther) both featured in the "Gran Turismo" movie the year prior to this series. The pair appear to have gone straight from filming that movie, to this television series.
This is the second time Marc Warren and Lu Corfield have worked together. The first being briefly on Van der Valk (Season 3, Episode 2) the year prior.
Rosie Sheehy (Elan Parry) and Oliver Ryan (Mihangel Pugh) both appear in this series, having also appeared in "The Steeltown Murders" in 2023