Paul Fix was born in Dobbs Ferry, New York, to Wilhelm Fix, a brewmaster, and the former Louise C. Walz,[citation needed] though some sources say he was born Paul Fix Morrison His mother and father were German immigrants who had left their Black Forest home and arrived in New York City in the 1870s. A veteran of the United States Navy during World War I, Fix became a busy character actor who obtained his start in local productions in New York. By the 1920s, he had moved to Hollywood, and performed in the first of almost 350 movie and television appearances. In the 1930s, he became friends with John Wayne. He was Wayne’s acting coach and eventually appeared as a featured player in about 27 of Wayne’s films. Paul Fix worked in early films such as Lucky Star (1929) and Ladies Love Brutes (1930), and became a regular performer for the film’s director, Frank Borzage, on a further eight occasions. Fix later appeared as Richard Bravo in the 1950s cult classic, The Bad Seed (1956), The Sea Chase (1955) playing Heinz the cook, and in George Stevens’ Giant (1956), playing Elizabeth Taylor’s father. Though Fix is best-remembered for his recurring role as Marshal Micah Torrance on ABC’s The Rifleman, he also worked in many other series in guest-starring roles. On February 28, 1958, he appeared with Edd Byrnes as Frank Wilson, Sr., and Frank, Jr., respectively in the episode “The Golden Gun” on the ABC/Warner Brothers, western series, Colt .45, starring Wayde Preston. Ron Hayes, Charles Fredericks, and Stuart Randall also appeared in this episode. Seven months later, Byrnes was cast in the new 77 Sunset Strip ABC/WB production.

On Christmas Day, 1958, Paul Fix appeared in the episode “Medal for Valor” on CBS’s Dick Powell’s Zane Grey Theater. Fix plays Rufus Stewart, a businessman who hires David Manning, played by Richard Basehart, a man with an ill wife who is in need of medical treatment, to substitute in the American Civil War for Stewart’s son, Adam’, portrayed by Richard Anderson. Manning, who won a Medal of Honor, returns from three years in the United States Army with an affidavit certifying that he was a military substitute so that he can claim western land. Rufus Stewart reneges on the promise because the son, the local sheriff, is running for the United States House of Representatives. Oddly, Rufus ends up being shot to death in a confrontation that he caused, and Adam agrees to provide the affidavit to Manning. The episode does not reveal if the sheriff was elected to Congress but considers the political liability of one having hired a substitute in the war. Paul Fix guest-starred on the short-lived detective series, Meet McGraw and on the western series of Rory Calhoun and John Payne, The Texan and The Restless Gun, which aired, respectively, in the same time slot on Mondays on CBS and NBC. Paul Fix played the historical role of U.S. President Zachary Taylor in the 1960 episode “That Taylor Affair” of the NBC western series, Riverboat, with Darren McGavin. Arlene Dahl was cast in this episode as Lucy Belle.

In 1961, Paul Fix appeared as Ramsey Collins in the series finale, “Around the Dark Corner”, of the NBC crime drama Dante. That same year he played Dr. Abel in the episode “The Haven” on The DuPont Show with June Allyson. Other television credits included Adventures of Superman (1953–1954, with Anthony Caruso and Elisha Cook, Jr.) and the adventure series, Northwest Passage. Fix played Dr. Mark Piper, Leonard McCoy’s predecessor in the second pilot episode of Star Trek, “Where No Man Has Gone Before”. When NBC picked up Star Trek as a series in 1966, Fix was replaced as the Enterprise medical officer by DeForest Kelley in the role of Dr. Leonard “Bones” McCoy. Paul Fix appeared as the presiding judge in To Kill a Mockingbird (1962). He played the sheriff in The Sons of Katie Elder. In 1966, he appeared in the film El Dorado. In 1972 he appeared in the film Night of the Lepus. In 1979, he appeared in Wanda Nevada. Fix co-wrote the screenplay for the John Wayne film Tall in the Saddle.

Paul Fix made five appearances as District Attorney Hale on Perry Mason (1957–1963), showing great skill as an examiner who did not ask objectionable questions unlike Hamilton Burger, who often experienced a judge’s ire for asking leading questions. He guest-starred on such television series as The Twilight Zone (1964), The F.B.I. (1965–1973), Voyage to the Bottom of the Sea (1966), The Time Tunnel (1966), The Wild Wild West (1966–1967), Daniel Boone (1969), Owen Marshall: Counselor at Law (1971), The Rockford Files episode “The House on Willis Avenue” (as Joe Tooley), and two episodes of The Streets of San Francisco, one in 1973 and again in 1975, each a different character/storyline. He appeared on the NBC series Kentucky Jones (1964) as Judge Perkins in the episode “Spare the Rod”. He played an aging suicidal novelist named Maxwell Hart on the Emergency! episode “Kidding”, where Paramedic John Gage, played by Randolph Mantooth, was in charge of a small group of intellectual 10 and 11-year-old school children on a tour of Rampart General Hospital. He played the role of New Mexico rancher Pete Maxwell in the 1973 film Pat Garrett and Billy the Kid. In 1974, he made an appearance as an old friend of Steve Austin’s in the TV series The Six Million Dollar Man in the episode “Population Zero”. He also appeared as Kronus, a retired fleet commander on the original Battlestar Galactica.

Paul Fix played the hardy pioneer James Briton “Brit” Bailey in the 1969 episode “Here Stands Bailey” of the syndicated series Death Valley Days, hosted by Robert Taylor not long before Taylor’s own death. In the storyline, Bailey and his second wife, Hannah (Rosemary DeCamp), make their final settlement in southeastern Texas after having overcome many obstacles over the years. Now they face Stephen F. Austin (John Carter) with an order that they leave the land reserved for the Old Three Hundred original families of Texas. Soon Austin has a change of heart and asks them to stay. Bailey dies with his final wish of interment standing upright facing west, hence his grave marker, “Here Stands Bailey Facing West.” Paul Fix died of renal failure in Los Angeles, at the age of eighty-two.