Filmography
| Role | Title | Year | Character |
|---|---|---|---|
| Writer | The Tourist | 2010 | |
| Writer | Downtown Abbey | 2019 | |
| Producer | Downtown Abbey | 2019 | |
| Actor | Tomorrow Never Dies | 1997 | Minister of Defence |
| Writer | Downton Abbey: A New Era | 2022 | |
| Writer | Romeo & Juliet | 2013 | |
| Writer | Titanic (2012) | ||
| Writer | The Young Victoria | 2009 | |
| Writer | Crooked House | 2017 | |
| Actor | House of Cards | Sir Henry Ponsonby | |
| Writer | Gosford Park | 2001 | |
| Producer | Gosford Park | 2001 | |
| Writer | Vanity Fair | 2004 | |
| Actor | Goldeneye | 1989 | Noel Coward |
| Actor | Damage | 1992 | Donald Lyndsay, MP |
| Director | From Time to Time | 2009 | |
| Writer | From Time to Time | 2009 | |
| Producer | From Time to Time | 2009 | |
| Actor | Monarch of the Glen | Lord Kilwillie | |
| Actor | Shadowlands | 1993 | Desmond Arding |
| Actor | Aristocrats | Duke of Richmond | |
| Actor | Our Friends in the North | ||
| Writer | The Chaperone | 2019 | |
| Actor | A Christmas Star | 2017 | Himself |
| Actor | The Scarlet Pimpernel | 1982 | The Prince Regent |
| Director | Separate Lies | 2005 | |
| Actor | Place Vendome | 1998 | Wajman |
| Actor | Sharpe's Rifles | 1993 | Major Dunnett |
| Actor | Baby: Secret of the Lost Legend | 1985 | Nigel Jenkins |
| Actor | Regeneration | 1997 | Timmons |
| Actor | Sharpe's Regiment | 1996 | The Prince Regent |
| Actor | The Bunker | 1981 | Co. von Below |
| Actor | Florence Nightingale | 1985 | Charles Bracebrige |