George C. Scott

Character: Dan Charles Logan

Richard Basehart

Character: Dr. Roy Caldwell

Martin Sheen

Character: Maj. Holliford

Barnard Hughes

Character: Dr. Spencer

Nicolas Beauvy

Character: Chris Logan

Paul Stevens

Character: Col. William Franklin

Stephen Young

Character: Major Reintz

Kenneth Tobey

Character: Col. Alan A. Nickerson

Robert Walden

Character: Dr. Janeway

William Jordan

Character: Major Cooper

Dabbs Greer

Character: Dr. Thompson

John Dierkes

Character: Bill Parker

Bette Henritze

Character: Sarah Parker

Lou Frizzell

Character: Dr. Spike Boynton

Ed Lauter

Character: Simpson

Phoebe Noel

Character: Waitress

Steve DeFrance

Character: Ambulance Driver (uncredited)

Anna Aries

Character: Bit Part

Fielding Greaves

Character: Dr. Walter Steenrod, Chivington Research Laboratories

Terry Wilson

Character: Kaufman Trucking Co. driver