Peter Graves was born Peter Duesler Aurness on March 18, 1926, in Minneapolis, Minnesota, the son of parents Rolf Cirkler Aurness (1894–1982), a businessman, and his wife Ruth (née Duesler, died 1986), a journalist. Graves’ ancestry was Norwegian, German, and English. The family name originally was “Aursnes,” but when Rolf’s Norwegian father, Peter Aursnes, immigrated to New York City in 1887, he changed the spelling. Peter used the stage name “Graves”, a maternal family name. He used the name Graves to honor his mother’s family, and also so as to not be confused with his older brother, James Arness, who was the star of the television series Gunsmoke.  Graves graduated from Southwest High School in 1944, and spent two years in the United States Army Air Forces near the end of World War II. He then enrolled at the University of Minnesota on the G.I. Bill, and was a member of Phi Kappa Psi fraternity.  Graves appeared in more than seventy films, television shows, and television movies during his career. In 1955, Graves joined the NBC television series Fury, as the rancher and adoptive single father, Jim Newton. Graves also was featured in the 1953 World War II film, Stalag 17.

From 1960-61 Graves starred as leading character Christopher Cobb in 34 episodes of the TV series Whiplash. In the story line Cobb is an American who arrives in Australia in the 1850s to establish the country’s first stagecoach line, using a bullwhip rather than a gun to fight the crooks that he encounters. The series also starred Anthony Wickert. Graves also starred in the British made ITC series Court Martial playing U.S. Army Lawyer Major Frank Whittaker (one of the series two American Leads starring opposite Bradford Dillman’s Captain David Young ) as well as guest roles in such series as Alfred Hitchcock Presents, Cimarron City, Route 66 and The Invaders,(episode; ‘Moonshot’) In 1967, Graves was recruited by Desilu Studios to replace Steven Hill as the lead actor on Mission: Impossible. Graves portrayed the iconic character of James Phelps, the sometimes-gruff director of the Impossible Missions Force or IMF, for the six following seasons of the series.[5][6] After the series ended in 1973, Graves played a cameo-type support role in the feature film Sidecar Racers in Australia which was released in 1975. Graves also made a guest appearance in the teen soap opera Class of ’74 in mid-1974, playing himself.

Graves was cast as Palmer Kirby in the 1983 ABC miniseries, The Winds of War. He played opposite Robert Mitchum, Jan Michael Vincent, Deborah Winters and Ali MacGraw in what became in ’83, the second most watched miniseries of all time (after Roots).  After playing mainly serious roles in the 1970s, he appeared as Captain Clarence Oveur in the early 80s comedies Airplane! and Airplane II: The Sequel.

In 1988 a Hollywood writers’ strike resulted in a new Mission: Impossible series being commissioned. Graves was the only original cast member to return as a regular, reprising his role as James Phelps, though other original cast members (most notably Greg Morris, whose son Phil was a regular in this version) made guest appearances. The series was filmed in Australia, and Graves made his third journey there for acting work. The new version of Mission: Impossible lasted for two seasons, ending in 1990. Bookending his work on Mission: Impossible, Graves starred in two pilot films called Call to Danger, which were an attempt to create a Mission: Impossible-style series in which Graves played a government agent (the Bureau of National Resources) who recruited civilians with special talents for secret missions.  The 1960s version of the pilot, according to Patrick White in The Complete Mission: Impossible Dossier (which White reports was actually the second such pilot, but Graves was not involved in the first), is credited with winning Graves the role of Phelps; after Mission: Impossible ended in 1973, Graves filmed a third version of the pilot (this one structured as a made-for-TV movie), but it did not sell as a series. The concept was later used in the brief 1980s adventure series Masquerade.

During the 1990s, he hosted and narrated the documentary series Biography on A&E. He also acted in a number of films featured on Mystery Science Theater 3000, which subsequently featured running jokes about Graves’s Biography work and presumed sibling rivalry with Arness. The films that have been featured on Mystery Science Theater 3000 include SST: Death Flight, It Conquered the World, Beginning of the End, Parts: The Clonus Horror, and an uncredited voiceover in The Eye Creatures. The film Killers from Space was featured in The Film Crew, Michael J. Nelson’s follow-up to MST3K. Graves himself parodied his Biography work in the film Men in Black II, hosting an exposé television show. He also played Colonel John Camden on the television series 7th Heaven. In 1995, Graves starred with Charlton Heston, Mickey Rooney and Deborah Winters in the Warren Chaney docudrama, America: A Call to Greatness.

In the 1996 film update of Mission: Impossible, the character of Phelps (played by Jon Voight, Graves had refused to play the role) was re-imagined as a traitor who murders three fellow IMF agents only to be killed himself at the end of the film, a decision that disappointed Graves, as well as many fans of the original series.  On October 30, 2009, Graves was honored with a star on the Hollywood Walk of Fame.  AirTran Airways featured Graves in a series of web-only “Internetiquette” videos in 2009 in which Graves appeared in a pilot’s uniform and references classic Airplane! lines. The videos were part of an AirTran Airways campaign to promote their in-flight wireless Internet access.  In the summer of 2009 Graves signed on as a spokesman for reverse mortgage lender American Advisors Group (AAG). Graves appeared in a national commercial in which he marketed reverse mortgages.  Graves’ final project was narrating the computer game epic Darkstar: The Interactive Movie, released November 5, 2010.  After returning from a brunch on March 14, 2010, Graves collapsed and died of a heart attack at the age of 83, four days before his 84th birthday.