Scott became a company member at Peninsula Players Theatre in Fish Creek in 1950, Wisconsin using the name Dan Scott prior to his Hollywood success. He performed in many stage productions with the theater, including the 1948 production of The Second Man, the 1950 production of You Can't Take it With You and the 1963 production of The Night of the Iguana.
Scott starred in the early episodes of Markham as John Riggs, the title character's sidekick. However the character of Riggs was dropped after only eight episodes.
Scott made five guest appearances on Perry Mason, including the role of murderer Stanley Overton in one of the series' final episodes in 1966 titled "The Case of the Positive Negative". He also appeared on dozens of other TV series, making numerous appearances each on series including 77 Sunset Strip, Bonanza, The F.B.I., 1973 Cannon, The Invaders, and Ironside. Scott also played in Barnaby Jones, in an episode titled “Trap Play”(01/07/1975).
1958: Perry Mason 1x39 The Case of the Rolling Bones as George Metcalf, 3x06 The Case of Paul Drake's Dilemma as Charles Dameron, 5x22 The Case of the Crippled Cougar as Elliot Dunbar, 8x03 The Case of the Scandalous Sculptor as Rex Ainsley, 9x28 The Case of the Positive Negative as Stanley Overton
1959–1968: Bonanza 1x13 Vendetta as Tom Pryor, 3x20 Lost Yesterday as Trev Holcomb, 5x09 Dead-Eye Dick as District Attorney, 7x14 All Ye His Saints as Evan Thorpe (1965), 9x22 The Late Ben Cartwright as Judge John Farraday (1968)
1962: Going My Way 1x08 A Matter of Principle as Larry Raymond
1961–1963: 77 Sunset Strip 4x13 "The Navy Caper" as Captain Bill Ivers, 4x21 "Brass Ring Caper" as Brad Kalem, 5x01 "The Reluctant Spy" as Hank Rush, 5x15 "Scream Softly, Dear" as Warren Collins
1965: Death Valley Days 14x07 No Place for a Lady as Samuel Magoffin
1965: Convoy 1x02 Flight from Norway as General Walther Korsch
1965–1966: McHale's Navy 4x07 The Bald-Headed Contessa, 4x08 Voltafiore Fish-Fry, 4x11 The McHale Opera Company, 4x13 Blitzkrieg at McHale's Beach, 4x16 The Boy Scouts of 73, 4x17 Fire in the Liquor Locker, 4x21 McHale's Country Club Caper, 4x22 Secret Chimp 007, 4x27 The McHale Grand Prix, all as General Bronson
1966: T.H.E. Cat 1x10 To Bell T.H.E. Cat as Senator
1966: The Munsters 2x31 Herman's Lawsuit as Wilbur Kingsley
1966: The Fugitive 4x05 Ten Thousand Pieces of Silver as Martin Pierce
1966–1968: The Wild Wild West 1x24 The Night of the Druid's Blood as Colonel Fairchild, 2x02 The Night of the Golden Cobra as Colonel Stanton Mayo, 4x03 The Night of the Juggernaut as Theodore Bock
1966–1969: The F.B.I. 1x24 The Man Who Went Mad by Mistake as John Goddard, 2x19 The Gray Passenger as Colfax, 3x01 The Gold Card as Aaron Kellin, 3x16 Crisis Ground as Talbot, 4x02 Out of Control as Douglas Benson, 5x06 Gamble with Death as Alexander York
1967: Iron Horse 2x09 Four Guns to Scalplock as Glenn Falconer
1967: Ironside 1x04 Dead Man's Tale as Warren Stuart, 1x15 Girl in the night as Jim Cardoff, 2x01 Shell Game as Waltham, 3x13 Beyond a shadow as John Lovell, 4x10 The man on the inside as Carmine De Bello
1967–1968: The Invaders 1x12 Storm as Dr. Ed Gantley / Professor Malcolm Gantley, 2x01 Condition: Red as Major Pete Stanhope, 2x19 The Pit as Dr. John Slaton
1968: The Outsider 1x13 There Was a Little Girl as George Harrington
1971: Days of Rage 1x24 Days of Rage as Walter Hendricks
1972: Longstreet 1x23 The Sound of Money Talking as Henry Benton
1972: The Sixth Sense 1x05 The Man Who Died at Three and Nine as Stuart Forbes
1972–1976: Cannon 2x12 The Endangered Species as Bill Coates (1972), 2x23 Press Pass to the Slammer, 3x12 Trial by Terror, 4x08 A Killing in the Family, 5x21 The Quasar Kill as Dr. Lawrence (1976), 5x25 Madman as General Stevenson
1972–1976: The Rookies 1x07 The Bear That Didn't Get Up as Mr. Palmer
1973: Search 1x21 Ends of the Earth as Timothy Slater
