| Hugh Bonneville | Robert Crawley, Earl of Grantham |
| Laura Carmichael | Lady Edith Crawley |
| Jim Carter | Charles Carson |
| Brendan Coyle | John Bates |
| Michelle Dockery | Lady Mary Crawley |
| Siobhan Finneran | Sarah O'Brien |
| Joanne Froggatt | Anna Bates |
| Robert James-Collier | Thomas Barrow
(as Rob James-Collier) |
| Phyllis Logan | Mrs. Hughes |
| Elizabeth McGovern | Cora Crawley, Countess of Grantham |
| Sophie McShera | Daisy Mason |
| Lesley Nicol | Mrs. Patmore |
| Maggie Smith | Violet Crawley, Dowager Countess of Grantham |
| Dan Stevens | Matthew Crawley |
| Penelope Wilton | Isobel Crawley |
| Robert Bathurst | Sir Anthony Strallan |
| Samantha Bond | Lady Rosamund Painswick |
| Timothy Carlton | Judge |
| Paul Copley | Mr. Mason |
| Jonathan Coy | George Murray |
| Iain Glen | Sir Richard Carlisle |
| Nigel Havers | Lord Hepworth |
| Dominic Kemp | Jury Foreman |
| Simon Poland | Defense Barrister |
| Tony Pritchard | Prison Officer |
| Nick Sampson | Prosecution Barrister |
| Sharon Small | Marigold Shore |
| Nicholas Blatt | Brookes, Sir Richards Valet
(uncredited) |
| Isis | Dog
(uncredited) |
| Teresa Mahoney | Villager
(uncredited) |