| Year | Title | Role | Notes |
| 1948 | Corridor of Mirrors | Charles | |
| One Night with You | Pirelli's Assistant | |
| Hamlet | Spear Carrier | Uncredited |
| A Song for Tomorrow | Auguste | |
| Penny and the Pownall Case | Jonathan Blair | |
| My Brother's Keeper | Second Constable | Scenes deleted |
| Saraband for Dead Lovers | Bit Part | Uncredited |
| Scott of the Antarctic | Bernard Day | |
| 1949 | Trottie True | Hon. Bongo Icklesham | |
| 1950 | They Were Not Divided | Chris Lewis | |
| Prelude to Fame | Newsman | |
| 1951 | Captain Horatio Hornblower R.N. | Spanish Captain | |
| Valley of Eagles | Det. Holt | |
| Quo Vadis | Chariot Driver | Uncredited[2] |
| 1952 | The Crimson Pirate | Joseph |
| Top Secret | Russian Agent |
| Paul Temple Returns | Sir Felix Raybourne | |
| Babes in Bagdad | Slave Dealer | |
| Moulin Rouge | Georges Seurat | Uncredited |
| 1953 | Les Vacances de Monsieur Hulot | Unknown (voice) |
| Innocents in Paris | Lieutenant Whitlock |
| 1954 | Destination Milan | Svenson | |
| 1955 | Cross-Roads | Harry Cooper | Short film |
| That Lady | Captain | |
| Final Column | Larry Spence | Archive footage |
| Man in Demand | Martell |
| Contraband Spain | Narrator | Uncredited |
| The Dark Avenger | French Patrol Captain at Tavern |
| The Cockleshell Heroes | Lt. Cdr. Dick Raikes, RN | |
| Alias John Preston | John Preston | |
| Police Dog | Police Constable Johnny | |
| Storm Over the Nile | Karaga Pasha | |
| 1956 | Private's Progress | Major Schultz | Uncredited |
| Alexander the Great | Nectenabus (voice) |
| Port Afrique | Franz Vermes | |
| Beyond Mombasa | Gil Rossi | |
| The Battle of the River Plate | Manolo | |
| 1957 | Ill Met by Moonlight | German Officer at Dentist's | |
| Fortune Is a Woman | Charles Highbury | |
| The Traitor | Dr. Neumann | |
| The Curse of Frankenstein | The Creature | |
| Manuela | Unknown (voice) | Uncredited |
| Bitter Victory | Sgt. Barney | |
| The Truth About Women | Francois Thiers | |
| 1958 | A Tale of Two Cities | Marquis St. Evremonde | |
| Dracula | Count Dracula | Alternative title: Horror of Dracula |
| Battle of the V-1 | Brunner | |
| Corridors of Blood | Resurrection Joe | |
| 1959 | The Hound of the Baskervilles | Sir Henry Baskerville | |
| The Man Who Could Cheat Death | Pierre Gerard | |
| The Treasure of San Teresa | Jaeger | |
| The Mummy | Kharis / The Mummy | |
| Uncle Was a Vampire | Baron Roderico da Frankurten | |
| 1960 | Too Hot to Handle | Novak | |
| The Two Faces of Dr. Jekyll | Paul Allen | Alternative titles: House of Fright and Jekyll's Inferno |
| Beat Girl | Kenny King | Alternative title: Wild for Kicks |
| The City of the Dead | Prof. Alan Driscoll | Alternative title: Horror Hotel |
| The Hands of Orlac | Nero the magician | |
| 1961 | The Terror of the Tongs | Chung King | |
| Taste of Fear | Doctor Pierre Gerrard | |
| The Devil's Daffodil | Ling Chu | |
| Hercules in the Haunted World | King Lico (Licos) | Alternative title: Ercole al centro della terra |
| 1962 | The Puzzle of the Red Orchid | Captain Allerman | Alternative title: The Secret of the Red Orchid |
| The Pirates of Blood River | Captain LaRoche | |
| The Devil's Agent | Baron von Staub | |
| Sherlock Holmes and the Deadly Necklace | Sherlock Holmes | |
| 1963 | Stranglehold | | |
| Katarsis | Mephistoles | Alternative title: Challenge the Devil |
| The Virgin of Nuremberg | Erich | Alternative titles: Castle of Terror and La vergine di Norimberga |
| La frusta e il corpo | Kurt Menliff | Alternative titles: The Whip and the Body and Night Is the Phantom |
| 1964 | Terror in the Crypt | Count Ludwig Karnstein | Alternative titles: Crypt of the Vampire and Crypt of Horror |
| The Devil-Ship Pirates | Captain Robeles | |
| Il castello dei morti vivi | Count Drago | Alternative title: Castle of the Living Dead |
| The Gorgon | Prof. Karl Meister | |
| 1965 | Dr Terror's House of Horrors | Franklyn Marsh | Segment: "Disembodied Hand" |
| She | Billali | |
| The Face of Fu Manchu | Dr. Fu Manchu | |
| The Skull | Sir Matthew Phillips | |
| Ten Little Indians | Mr. U.N. Owen (voice) | Uncredited |
| 1966 | Dracula: Prince of Darkness | Count Dracula | |
| Rasputin, the Mad Monk | Grigori Rasputin | |
| Circus of Fear | Gregor | Alternative title: Psycho Circus |
| The Brides of Fu Manchu | Dr. Fu Manchu | |
| 1967 | Five Golden Dragons | Dragon No. 4 | |
| The Vengeance of Fu Manchu | Dr. Fu Manchu | |
| Night of the Big Heat | Godfrey Hanson | |
| Theatre of Death | Philippe Darvas | |
| The Blood Demon | Count Frederic Regula / Graf von Andomai | Alternative titles: Die Schlangengrube Und Das Pendel and The Torture Chamber of Dr. Sadism |
| 1968 | Eve | Colonel Stuart | Alternative title: The Face of Eve |
| The Devil Rides Out | Duc de Richleau | Alternative title: The Devil's Bride |
| The Blood of Fu Manchu | Dr. Fu Manchu | |
| Dracula Has Risen from the Grave | Count Dracula | |
| Curse of the Crimson Altar | Morley | Alternative title: The Crimson Cult |
| 1969 | The Castle of Fu Manchu | Dr. Fu Manchu | |
| The Oblong Box | Dr J. Neuhart | |
| The Magic Christian | Ship's Vampire | |
| 1970 | Scream and Scream Again | Fremont | |
| Eugenie… The Story of Her Journey into Perversion | Dolmance | |
| The Bloody Judge | Lord George Jeffreys | Alternative title: Night of the Blood Monster |
| Count Dracula | Count Dracula | |
| Taste the Blood of Dracula | Count Dracula | |
| Julius Caesar | Artemidorus | |
| One More Time | The Vampire | Cameo |
| The Private Life of Sherlock Holmes | Mycroft Holmes | |
| Scars of Dracula | Count Dracula | |
| 1971 | The House That Dripped Blood | John Reid | Segment: "Sweets to the Sweet" |
| Cuadecuc, vampir | Count Dracula / Himself | |
| I, Monster | Dr. Charles Marlowe / Mr. Edward Blake | |
| Hannie Caulder | Bailey | |
| 1972 | Umbracle | The Man | |
| Dracula A.D. 1972 | Count Dracula | |
| Horror Express | Sir Alexander Saxton | |
| Death Line | Stratton-Villiers, MI5 | Alternative title: Raw Meat |
| 1973 | Nothing But the Night | Col. Charles Bingham | |
| The Creeping Flesh | James Hildern | |
| The Satanic Rites of Dracula | Count Dracula | |
| The Wicker Man | Lord Summerisle | [2] |
| The Three Musketeers | Rochefort | |
| 1974 | Dark Places | Dr. Mandeville | |
| The Four Musketeers | Rochefort | |
| The Man with the Golden Gun | Francisco Scaramanga | |
| 1975 | Le boucher, la star et l'orpheline | Van Krig / Himself | |
| In Search of Dracula | Narrator | |
| Diagnosis Murder | Stephen Hayward | |
| The Story of Heidi | Unknown (voice) | English dub |
| 1976 | Killer Force | Major Chilton | Alternative title: The Diamond Mercenaries |
| To the Devil, A Daughter | Father Michael Rayner | |
| Albino | Bill | Alternative titles: Whispering Death and Death in the Sun |
| Dracula père et fils | The Prince of Darkness | Alternative title: Dracula and Son |
| The Keeper | The Keeper | |
| 1977 | Airport '77 | Martin Wallace | |
| Meatcleaver Massacre | Narrator / Himself | Alternative titles: Evil Force and Revenge of the Dead |
| End of the World | Father Pergado / Zindar | |
| Starship Invasions | Captain Rameses | |
| 1978 | Circle of Iron | Zetan | Alternative title: The Silent Flute |
| Return from Witch Mountain | Victor Gannon | |
| Caravans | Sardar Khan | |
| 1979 | The Passage | Gypsy | |
| Captain America II: Death Too Soon | General Miguel | |
| Nutcracker Fantasy | Various voices | [4] |
| Arabian Adventure | Alquazar | |
| Jaguar Lives! | Adam Caine | |
| Bear Island | Lechinski | |
| 1941 | Capt. Wolfgang von Kleinschmidt | |
| 1980 | Serial | Luckman Skull | |
| Safari 3000 | Count Borgia | |
| 1981 | An Eye for an Eye | Morgan Canfield | |
| Desperate Moves | Carl Boxer | |
| The Salamander | Prince Baldasar | |
| 1982 | The Last Unicorn | King Haggard (voice) | |
| 1983 | House of the Long Shadows | Corrigan | |
| The Return of Captain Invincible | Mr. Midnight | |
| New Magic | Mr. Kellar | Short film |
| 1984 | The Rosebud Beach Hotel | Clifford King | |
| The Bengal Lancers! | Sir James Hunter | Unfinished film |
| 1985 | Howling II: Your Sister Is a Werewolf | Stefan Crosscoe | |
| Mask of Murder | Chief Supt. Jonathan Rich | |
| 1986 | Jocks | President White | |
| 1987 | Mio min Mio | Kato | |
| The Girl | Peter Storm | |
| 1988 | Dark Mission | Luis Morel | |
| Olympus Force: The Key | Filly | |
| 1989 | The Return of the Musketeers | Rochefort | |
| La Révolution française | Sanson | Segment: "Années Terribles, Les" |
| La chute des aigles | Walter Strauss | |
| Murder Story | Willard Hope | |
| Honeymoon Academy | Lazos | |
| 1990 | L'avaro | Cardinale Spinosi | |
| Gremlins 2: The New Batch | Doctor Catheter | |
| The Rainbow Thief | Uncle Rudolf | |
| 1991 | Kabuto | King Philip | |
| Curse III: Blood Sacrifice | Doctor Pearson | Alternative title: Panga |
| Jackpot | Cedric | |
| 1994 | Funny Man | Callum Chance | |
| Police Academy: Mission to Moscow | Cmndt. Alexander Nikolaevich Rakov | |
| A Feast at Midnight | V. E. Longfellow | |
| Flesh and Blood | Narrator / Himself | Documentary film |
| 1996 | The Stupids | Mr. Sender | |
| Welcome to the Discworld | Death (voice) | Short film |
| 1998 | Tale of the Mummy | Sir Richard Turkel | |
| Jinnah | Muhammad Ali Jinnah | [5] |
| 1999 | Sleepy Hollow | Burgomaster | |
| 2001 | The Lord of the Rings: The Fellowship of the Ring | Saruman | |
| 2002 | Star Wars: Episode II – Attack of the Clones | Count Dooku | |
| The Lord of the Rings: The Two Towers | Saruman | |
| 2003 | The Lord of the Rings: The Return of the King | Extended Edition only |
| 2004 | Crimson Rivers II: Angels of the Apocalypse | Heinrich von Garten | |
| 2005 | Star Wars: Episode III – Revenge of the Sith | Count Dooku | |
| Charlie and the Chocolate Factory | Dr. Wilbur Wonka | |
| The Adventures of Greyfriars Bobby | The Lord Provost | |
| Corpse Bride | Pastor Galswells (voice) | [4] |
| 2007 | The Golden Compass | First High Councillor | |
| 2008 | Star Wars: The Clone Wars | Count Dooku (voice) | [4] |
| 2009 | Boogie Woogie | Alfred Rhinegold | |
| The Heavy | Mr. Mason | |
| Triage | Joaquín Morales | |
| Glorious 39 | Walter | |
| 2010 | Alice in Wonderland | Jabberwock (voice) | [4] |
| Burke & Hare | Joseph | |
| 2011 | Season of the Witch | Cardinal d’Ambroise | |
| The Resident | August | |
| The Wicker Tree | Old Gentleman | |
| Grave Tales | Himself | Cameo |
| Hugo | Monsieur Labisse | |
| 2012 | Dark Shadows | Silas Clarney | |
| The Hobbit: An Unexpected Journey | Saruman | [6] |
| 2013 | Night Train to Lisbon | Father Bartolomeu | |
| Extraordinary Tales | Narrator | Segment: "The Fall of the House of Usher" |
| The Girl from Nagasaki | Old Officer Pinkerton | [7] |
| Necessary Evil: Super-Villains of DC Comics | Narrator | Documentary film[8] |
| 2014 | The Hobbit: The Battle of the Five Armies | Saruman | Final live-action role and final work released in his lifetime[9] |
| 2016 | Angels in Notting Hill | God / Mr. President (voice) | Posthumous release[10] |
| 2017 | The Hunting of the Snark | Narrator | Short film; posthumous release |
| 2024 | The Lord of the Rings: The War of the Rohirrim | Saruman (voice) | Archival recording; posthumous release[11] |