Timothy Spall John Chapel Actor Gwyneth Keyworth DS Janie Mallowan Actor Steffan Rhodri DCI Clarke Actor Alexandria Riley Helen Baxter Actor Rithvik Andugula DC Evan Chaudhry Actor Jim Howick Randall St Clair Actor Leisa Gwenllian Olivia Whitmore Actor Millicent Wong Magenta Mei Actor Camille Coduri Dawn Apsted Actor Jack Parry-Jones Emyr Davies Actor Amit Shah Ashwin Shaw Actor Paul Doolan Writer Madeline Addy Executive Producer Josh Cole Executive Producer Nikki Wilson Producer Sion Trefor Music Sian Harries Writer Claire Winyard Director