Peter Firth Harry Pearce Actor Hugh Simon Actor Nicola Walker Ruth Evershed Actor Rupert Penry-Jones Adam Carter Actor David Oyelowo Danny Hunter Actor Keeley Hawes Zoe Reynolds Actor Matthew Macfadyen Tom Quinn Actor Rory MacGregor Actor Shauna Macdonald Sam Buxton Actor Richard Harrington Actor Jalaal Hartley Guest Star Ian McDiarmid Guest Star Jonny Campbell Director Howard Brenton Writer Simon Crawford-Collins Executive Producer Jane Featherstone Executive Producer Gareth Neame Executive Producer Julie Scott Executive Producer