Conleth Hill Alan Conway Actor Lesley Manville Susan Ryeland Actor Mark Gatiss Frank Parris , Oscar Berlin Actor Pippa Bennett-Warner Madeline Cain Actor Tim McMullan Atticus Pünd Actor Daniel Mays Locke , Chubb Actor Adrian Rawlins Lawrence Treherne , Lance Gardner Actor Alexandros Logothetis Andreas Patakis Actor Anthony Horowitz Writer Jill Green Executive Producer Suzanne McAuley Producer Rae Hendrie Casting Rebecca Gatward Director