| The Cool School | Himself |
| "Captain Planet and the Planeteers" | Duke Nukem (voice) |
| "Greatest Heroes of the Bible" | Hissar |
| "Captain Planet and the Planeteers" | Duke Nukem (voice) |
| Bud Abbott and Lou Costello in Hollywood | Himself (uncredited) |
| Anchors Aweigh | Donald Martin |
| The Valley of Decision | Paulie Scott |
| The Green Years | Robert Shannon, as a child |
| Home, Sweet Homicide | Archie Carstairs |
| The Mighty McGurk | Nipper |
| The Arnelo Affair | Ricky Parkson |
| Gentleman's Agreement | Tommy Green |
| The Romance of Rosy Ridge | Andrew MacBean |
| Song of the Thin Man | Nick Charles Jr. |
| The Boy with Green Hair | Peter Fry |
| Deep Waters | Donny Mitchell |
| Al's Beef | The Sheriff |
| Down to the Sea in Ships | Jed Joy |
| The Secret Garden | Colin Craven |
| The Happy Years | John Humperdink 'Dink' Stover |
| Kim | Kim |
| Stars in My Crown | John Kenyon |
| Cattle Drive | Chester Graham, Jr. |
| "General Electric Theater" | Clete / ... (2 episodes, 1958-1959) |
| "Matinee Theatre" | (4 episodes, 1956) |
| Gun for a Coward | Hade (Harry) Keough |
| "Wagon Train" | Jimmy Owens / ... (4 episodes, 1957-1961) |
| The Careless Years | Jerry Vernon |
| Compulsion | Judd Steiner |
| Sons and Lovers | Paul Morel |
| "The Dick Powell Show" | Gary Harper / ... (2 episodes, 1961-1962) |
| "Dr. Kildare" | Dr. Rudy Devereux |
| Long Day's Journey Into Night | Edmund Tyrone |
| "The F.B.I." | Darryl Ryder / ... (2 episodes, 1968-1972) |
| Rapture | Joseph |
| Psych-Out | Dave |
| The Dunwich Horror | Wilbur Whateley |
| The Failing of Raymond | Raymond |
| The Last Movie | Billy |
| Paper Man | Avery Jensen |
| "The Streets of San Francisco" | Charlie Blake / ... (2 episodes, 1973-1975) |
| Adventures of Nick Carter | Freddy Duncan |
| Columbo: The Most Crucial Game | Eric Wagner |
| The Loners | Stein |
| "Police Story" | Bennett / ... (4 episodes, 1973-1976) |
| The Werewolf of Washington | Jack Whittier |
| Win, Place or Steal | Billy |
| Eadweard Muybridge, Zoopraxographer | Narrator |
| "Three for the Road" | Ethan Crawford (1 episode, 1975) |
| Columbo: Troubled Waters | Lloyd Harrington |
| Cop on the Beat | Det. Callan |
| The Pacific Connection | |
| One Away | |
| Tracks | Mark |
| Won Ton Ton, the Dog Who Saved Hollywood | Paul Lavell |
| A Killing Affair | Kenneth Switzer |
| She Came to the Valley | Pat Westall |
| "Greatest Heroes of the Bible" | Hissar (1 episode, 1978) |
| Born to Be Sold | Marty Helick |
| Alsino y el cóndor | Frank |
| Neil Young: Human Highway | |
| Neil Young: Human Highway | |
| Neil Young: Human Highway | Otto Quartz |
| Wrong Is Right | Chief of Staff Hacker |
| Dune | Dr. Wellington Yueh |
| Paris, Texas | Walt Henderson |
| The Legend of Billie Jean | Muldaur |
| Papa Was a Preacher | John |
| To Kill a Stranger | John Carver |
| To Live and Die in L.A. | Bob Grimes |
| Blue Velvet | Ben |
| Beverly Hills Cop II | Charles 'Chip' Cain |
| Gardens of Stone | Capt. Homer Thomas |
| Kenny Rogers as The Gambler, Part III: The Legend Continues | James McLaughlin |
| The Time Guardian | Boss |
| The Blue Iguana | Detective Carl Strick |
| Married to the Mob | Tony 'The Tiger' Russo |
| Palais Royale | Michael Dattalico |
| Tucker: The Man and His Dream | Howard Hughes |
| "Quantum Leap" | Admiral Al Calavicci |
| Catchfire | John Luponi |
| Buying Time | Detective Novak |
| Limit Up | Peter Oak |
| The Pacific Connection | |
| "Captain Planet and the Planeteers" | Duke Nukem (unknown episodes, 1990-1992) |
| Sandino | Capitain Hatfield |
| Son of the Morning Star | Gen. Philip Sheridan |
| Fatal Memories | Det. Robert Morse |
| Friends and Enemies | Freddie |
| The Player | Andy Civella |
| Shame | Tim Curtis |
| "Snowy River: The McGregor Saga" | Professor Julius Waugh |
| Bonanza: The Return | Augustus Brandenburg |
| Chasers | Salesman Stig |
| In the Line of Duty: The Price of Vengeance | Jack Lowe |
| The Innocent | Capt. Jason Flaboe |
| Justice in a Small Town | Commissioner Sam Caldwell |
| Madonna: Innocence Lost | Tony Ciccone |
| Vanishing Son II | Mickey Jo |
| "JAG" | SecNav Edward Sheffield |
| The Langoliers | Bob Jenkins |
| Deadline for Murder: From the Files of Edna Buchanan | Aaron Bliss |
| Naked Souls | Duncan |
| Midnight Blue | Katz-Feeney |
| Mr. Wrong | Jack Tramonte |
| Twilight Man | Hollis Deitz |
| Unabomber: The True Story | Ben Jeffries |
| "The Tony Danza Show" | Frank DiMeo (unknown episodes) |
| Air Force One | Defense Secretary Walter Dean |
| Close to Danger | Dr. Ames |
| Last Resort | Grey Wolf |
| Living in Peril | William |
| McHale's Navy | Capt. Wallace B. Binghampton |
| The Rainmaker | Judge Harvey Hale |
| The Shadow Men | Stan Mills |
| A Really Important Person | Billy Reilly |
| Sinbad: The Battle of the Dark Knights | Bophisto |
| "Hammer House of Mystery and Suspense" | Greg Denver (1 episode, 1986) |
| "It's True" | Mr. Murphy (1 episode, 1998) |
| "Captain Planet and the Planeteers" | Duke Nukem (unknown episodes, 1990-1992) |
| "Great Mysteries" | Jerry (1 episode, 1973) |
| Restraining Order | Charlie Mason |
| Restraining Order | Charlie Mason |
| Rites of Passage | Del Farraday |
| Jorge, um Brasileiro | Mario |
| Jorge, um Brasileiro | Mario |
| Banzai Runner | Billy Baxter |
| Water Damage | Det. Frank Skoufaris |
| Pretty as a Picture: The Art of David Lynch | Himself |
| In Pursuit | Charles Welz |
| The Venice Project | Senator Campbell |
| What Katy Did | Tramp |
| They Nest | Sheriff Hobbs |
| "Phenomenon: The Lost Archives" | Host / ... (14 episodes, 1998-2000) |
| Batman Beyond: Return of the Joker | Communications Engineer Mr. Timothy 'Tim' Drake |
| The Quickie | Michael |
| The Flunky | Micky |
| Buffalo Soldiers | General Lancaster |
| CQ | Dr. Ballard |
| Face to Face | Jimmy |
| The American Film Institute Salute to Gregory Peck | Himself |
| Caught in the Act | Host |
| Inferno | Mayor Bill Klinger |
| "Popular Science" | Host |
| "First Monday" | Senator Edward Sheffield |
| 8th Annual Screen Actors Guild Awards | Himself (archive footage) |
| Crazy About the Movies: Dennis Hopper | Himself |
| The Manchurian Candidate | Mark Whiting |
| Some of the Best | Himself (uncredited) |
| "Battlestar Galactica" | Brother Cavil |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
| "Phenomenon: The Lost Archives" | Host |
