Olivia Colman
as Susan Edwards
David Thewlis
as Christopher Edwards
Kate O'Flynn
as DC Emma Lancing
Dipo Ola
as Douglas Hylton
Daniel Rigby
as DCI Geoff Collier
Samuel Anderson
as DC Paul Wilkie
Felicity Montagu
as Patricia Wycherley
David Hayman
as William Wycherley