| Glenn Close | Lady Edith |
| Max Irons | Charles Hayward |
| Christina Hendricks | Brenda |
| Gillian Anderson | Magda |
| Terence Stamp | Chief Inspector Taverner |
| Stefanie Martini | Sophia deHaviland |
| Honor Kneafsey | Josephine |
| Amanda Abbington | Clemency Leonides |
| Christian McKay | Roger Leonides |
| Julian Sands | Philip Leonides |
| Roger Ashton-Griffiths | Gaitskill |
| John Heffernan | Laurence Brown |
| Preston Nyman | Eustace |
| Jenny Galloway | Nanny |
| Madeleine Hyland | Roger Leonide's Secretary |
| Petros L. Ioannou | Tommy Boy |
| David Cann | Coroner |
| Gino Picciano | Aristide |
| Andreas Karras | Iannois Agrodopolous |
| Jacob Fortune-Lloyd | Brent |
Technical Credits
| Gilles Paquet-Brenner | Director,Screenwriter |
| Joseph Abrams | Producer |
| Andrew Boswell | Executive Producer |
| Simon Bowles | Production Designer |
| Natalie Brenner | Executive Producer |
| Paul Carter | Sound/Sound Designer |
| Peter Christelis | Editor |
| Hugo DeChaire | Score Composer |
| York Entertainment | Executive Producer |
| Anders Erden | Executive Producer |
| Julian Fellowes | Screenwriter |
| Jay Firestone | Executive Producer |
| Mark Hedges | Asst. Director |
| Tim Hollier | Musical Direction/Supervision |
| Jane Hooks | Co-producer |
| Phil Hunt | Executive Producer |
| Cat Johnstone | Makeup |
| Colleen Kelsall | Costumes/Costume Designer |
| Simon Lamont | Art Director |
| David Lascelles | Sound Mixer |
| Will Machin | Executive Producer |
| Sarah Nuth | Makeup |
| Stewart Peter | Executive Producer |
| Reg Poerscout-Edgerton | Casting |
| Emily Precious | Associate Producer |
| Tim Rose Price | Screenwriter |
| Compton Ross | Executive Producer |
| Tim Smith | Executive Producer |
| James Spring | Producer |
| John Story | Executive Producer |
| James Swarbrick | Executive Producer |
| Sunny Vohra | Executive Producer |
| Sebastian Wintero | Cinematographer |
| Lisa Wolofsky | Executive Producer |
| Sally Wood | Producer |
| David Wood | Art Director |
