| Year | Film | Role | Other notes |
|---|
| 1956 | Ransom! | Charlie Telfer | Film debut |
| Forbidden Planet | Commander John J. Adams | |
| The Vagabond King | Thibault | |
| The Opposite Sex | Steve Hilliard | |
| 1957 | Hot Summer Night | William Joel Partain | |
| Tammy and the Bachelor | Peter Brent | |
| 1958 | The Sheepman | Col. Stephen Bedford/Johnny Bledsoe | |
| 1964 | See How They Run | Elliot Green | First television movie |
| Night Train to Paris | Alan Holiday | |
| 1965 | Dark Intruder | Brett Kingsford | |
| Harlow | Richard Manley | |
| 1966 | The Plainsman | Col. George Armstrong Custer | |
| Beau Geste | Lieutenant De Ruse | |
| 1967 | Code Name: Heraclitus | Fryer | |
| The Reluctant Astronaut | Major Fred Gifford | |
| Gunfight in Abilene | Grant Evers | |
| Rosie! | Cabot Shaw | |
| 1968 | How to Steal the World | General Maximilian Harmon | The Man From U.N.C.L.E. film |
| Counterpoint | Victor Rice | |
| Dayton's Devils | Frank Dayton | |
| Companions in Nightmare | Dr. Neesden | |
| 1969 | Trial Run | Jason Harkness | |
| Deadlock | Lieutenant Sam Danforth | |
| How to Commit Marriage | Phil Fletcher | |
| Change of Mind | Sherrif Webb | |
| 1970 | Night Slaves | Sherrif Henshaw | |
| The Aquarians | Official | |
| Hauser's Memory | Joseph Slaughter | |
| 1971 | Incident In San Francisco | Lieutenant Brubaker | |
| Four Rode Out | Mr. Brown | |
| They Call It Murder | Frank Antrim | |
| 1972 | The Poseidon Adventure | Captain Harrison | |
| 1973 | ...And Millions Die! | Jack Gallagher | |
| Snatched | Bill Sutting | |
| Amanda Fallon | Mr. Cummings | |
| The Return Of Charlie Chan | Alexander Hadrachi | |
| 1975 | Can Ellen Be Saved | Arnold Lindsey | |
| Threshold: The Blue Angels Experience | Narrator | |
| 1976 | Grand Jury | John Williams | |
| Project: Kill | Jonathan Trevor | |
| Brinks: The Great Robbery | Agent Norman Houston | |
| 1977 | Sixth and Main | John Doe | |
| Day of the Animals | Paul Jenson | |
| Viva Knievel! | Stanley Millard | |
| The Kentucky Fried Movie | Man in Feel-O-Rama Movie | Uncredited cameo; Feel-O-Rama segment |
| The Amsterdam Kill | Riley Knight | |
| 1978 | Little Mo | Nelson Fisher | |
| 1979 | Institute for Revenge | Counselor Hollis Barnes | |
| The Albertans | Don MacIntosh | |
| Riel | Major Crozier | |
| City on Fire | Mayor William Dudley | |
| 1980 | OHMS | Governor | |
| Airplane! | Dr. Rumack | First comedy role |
| Prom Night | Mr. Raymond Hammond | |
| 1981 | A Choice of Two | Unknown | |
| 1982 | Twilight Theater | Various Characters | |
| Foxfire Light | Reece Morgan | |
| Wrong Is Right | Mallory | |
| Creepshow | Richard Vickers | Something To Tide You Over segment |
| 1983 | Prime Times | Unknown | |
| The Night the Bridge Fell Down | Paul Warren | |
| Cave-In! | Joseph 'Joe' Johnson | |
| The Creature Wasn't Nice (Spaceship) | Capt. Jamieson | |
| 1985 | Murder Among Friends | Unknown | |
| Reckless Disregard | Bob Franklin | |
| Blade in Hong Kong | Harry Ingersoll | |
| Striker's Mountain | Jim McKay | |
| 1986 | The Patriot | Admiral Frazer | |
| Soul Man | Mr. Dunbar | |
| 1987 | Nightstick | Thad Evans | |
| Nuts | Allen Green | Final non-comedy role |
| Home Is Where The Hart Is | Sherrif Nashville Schwartz | |
| 1988 | Dangerous Curves | Greg Krevske | |
| The Railway Dragon | Narrator | First animated film |
| The Naked Gun: From the Files of Police Squad! | Lt. Frank Drebin | First starring role |
| 1990 | Repossessed | Father Jebedaiah Mayii | |
| 1991 | All I Want for Christmas | Santa Claus | Family holiday film |
| The Naked Gun 2½: The Smell of Fear | Lt. Frank Drebin | |
| Chance of A Lifetime | Lloyd Dixon | |
| 1993 | Digger | Arthur Evrensel | |
| Surf Ninjas | Colonel Chi | |
| 1994 | S.P.Q.R. 2000 e 1/2 anni fa | Lucio Cinico | |
| Naked Gun 33⅓: The Final Insult | Lt. Frank Drebin | |
| 1995 | Mr. Willowby's Christmas Tree | Willowby's butler | |
| Rent-a-Kid | Harry Haber | |
| Dracula: Dead and Loving It | Count Dracula | |
| 1996 | Spy Hard | Dick Steele, Agent WD-40 | |
| 1997 | Mr. Magoo | Mr. Magoo | |
| 1998 | Safety Patrol | Mr. Penn | |
| Family Plan | Harry Haber | |
| Harvey | Dr. Chumley | |
| Wrongfully Accused | Ryan Harrison | |
| 1999 | Pirates 4D | Captain Lucky | 4D Cinema Show at Thorpe Park, Surrey and Busch Gardens in Williamsburg, Virginia |
| 2000 | Santa Who? | Santa Claus | |
| 2001: A Space Travesty | Marshal Richard 'Dick' Dix | |
| 2001 | Camouflage | Jack Potter | |
| Kevin of the North (Chilly Dogs) | Clive Thornton | |
| 2002 | Men with Brooms | Gordon Cutter | |
| 2003 | Scary Movie 3 | President Harris | |
| Noël Noël | English Narrator | |
| 2006 | Scary Movie 4 | President Harris | |
| 2007 | Music Within | Bill Austin | |
| 2008 | Superhero Movie | Uncle Albert | |
| An American Carol | Grampa / Himself | |
| Slap Shot 3: The Junior League | Mayor of Charlestown | |
| 2009 | Spanish Movie | Doctor | |
| Stan Helsing | Kay | |
| 2010 | Slam I Am | Producer | |
| 2011 | The Waterman Movie | Ready Espanosa | Voice acting is complete.[74] |