Filmography
| Role | Title | Year | Character |
|---|---|---|---|
| Actor | Star Wars: Episodio IX - L'ascesa di Skywalker | 2019 | Emperor Palpatine |
| Actor | Star Wars: Episodio III - La vendetta dei Sith | 2005 | Supreme Chancellor Palpatine |
| Actor | Star Wars: Episodio I - La minaccia fantasma | 1999 | Senator Palpatine |
| Actor | Star Wars: Episodio II - L'attacco dei cloni | 2002 | Supreme Chancellor Palpatine |
| Actor | Star Wars: Episodio VI - Il ritorno dello Jedi | 1983 | The Emperor |
| Actor | Utopia | Anton | |
| Actor | Il mistero di Sleepy Hollow | 1999 | Doctor Lancaster |
| Actor | Britannia | King Pellenor | |
| Actor | Civiltà perduta | 2017 | Sir George Goldie |
| Actor | Elizabeth I | Lord Burghley | |
| Actor | Due figli di... | 1988 | Arthur |
| Actor | 37 Days | Edward Grey | |
| Actor | Il drago del lago di fuoco | 1981 | Brother Jacopus |
| Actor | Rebecca | Coroner | |
| Actor | Touching Evil | ||
| Actor | Gorky Park | 1983 | Professor Andreev |
| Actor | Charles II: The Power and the Passion | Sir Edward Hyde | |
| Actor | Restoration - Il peccato e il castigo | 1995 | Ambrose |
| Actor | Star Wars: Greatest Moments | 2015 | Himself |
| Actor | Le nuove avventure di Annie | 1995 | Dr. Eli Eon |
| Actor | Star Wars: Evolution of the Lightsaber Duel | 2015 | Himself |
| Actor | Sleepy Hollow: Behind the Legend | 2000 | Ian McDiarmid |
| Actor | City of Vice | Henry Fielding | |
| Actor | Star Wars: A Musical Journey | 2005 | Host |
| Actor | Crime and Punishment | 2002 | Porfiry |
| Actor | Alla 39ª eclisse | 1980 | Dr. Richter |
| Actor | Chernobyl - un grido dal mondo | 1991 | Dr. Vatisenko |
| Actor | How to Watch Star Wars, Part One: The Prequels Are Better Movies Than You Deserve | 2019 | Self (archive footage) |
| Actor | A Performance of Macbeth | 1979 | The Porter / Ross |