Sophia Carr-Gomm Catherine Ross Actor Rebecca Benson Sally Henry Actor Chris Reilly Alan Isbister Actor Douglas Henshall DI Jimmy Perez Actor Mark Bonnar Duncan Hunter Actor Brian Cox Magnus Bain Actor Erin Armstrong Cassie Perez Actor Cara Kelly Margaret Henry Actor Frances Grey Jess Collins Actor Julie Graham Rhona Kelly Actor Steven Robertson DC Sandy Wilson Actor Anne Kidd Cora McLean Actor Alison O'Donnell DS Alison 'Tosh' McIntosh Actor Matthew Zajac Alex Henry Actor Stewart Porter Sgt Billy McBride Actor Anthony Flanagan Ewan Ross Actor Tunji Kasim Hugo Scott Actor Finn Den Hertog Drew Actor John McKay Director Gaby Chiappe Writer