Anthony Horowitz Creator, Writer Ian Redford Sir Reginald Walker Actor Tim Preece Philby Actor Caroline Faber Agnes Browne Actor Laurence Fox Simon Walker Actor Michael Kitchen Christopher Foyle Actor Anthony Howell Paul Milner Actor Alan Howard Stephen Beck Actor Will Knightley Arthur Browne Actor Charlie G. Hawkins Brian Actor Honeysuckle Weeks Samantha Stewart Actor Barney Clark Tim Actor Geoffrey Freshwater Sergeant Rivers Actor Emily Blunt Lucy Markham Actor Luke de Woolfson Harry Markham Actor Christopher Benjamin Brigadier Harcourt Actor Richard Cotton Captain Devlin Actor Sarah Winman Lady Alice Walker Actor Darren Tighe Clarke Actor Tom Fisher Connor Actor Ian Barritt Vicar Actor Ellie Haddington Hilda Pierce Actor Jill Green Executive Producer Jim Reeve Executive Producer Giles Foster Director Michael Russell Writer