John Hillerman, a Texas-born actor who played the likably snobbish British caretaker on the television show “Magnum, P.I.” and held supporting roles in iconic 1970s movies like “Chinatown” and “Blazing Saddles,” died Thursday at his home in Houston. He was 84.
His publicist, Lori De Waal, said he had died of natural causes.

After 30 years of acting, on Broadway and in Hollywood, Mr. Hillerman landed a career-defining role in 1980 as Jonathan Quayle Higgins III, the stuffy perfectionist and foil to the free-spirited detective Thomas Magnum in “Magnum, P.I.” Higgins was grouchy with a sarcastic wit, not unlike Mr. Hillerman’s portrayal of a detective in the mid-1970s show “Ellery Queen.”

“Magnum, P.I.” became a runaway success for eight years for CBS and made Tom Selleck, who played Magnum, a mainstay in tabloids, solidifying his Hollywood career. But Mr. Hillerman relished the supporting role and found it equally rewarding.
“It isn’t so long ago that I was a struggling actor living in New York, and the only thing I could overlook was my rent,” Mr. Hillerman said in a 1985 interview, sipping a glass of wine on his penthouse balcony in Honolulu.

The portrayal of Higgins won him an Emmy Award for Best Supporting Actor in a Drama, a Golden Globe Award and many fans in England, who adored the haughty major-domo of a beachfront property where Magnum lived. Mr. Hillerman said he felt terrible when he responded to their fan mail and had to let them down.

“I hate to disappoint you, but I’m a hick from Texas,” he said he replied.
John Benedict Hillerman was born in Denison, Tex., about 60 miles north of Dallas, on Dec. 20, 1932, to Christopher Benedict Hillerman and Lenora Joan Hillerman. He was the middle child with two sisters, and he displayed independence at a young age. He is survived by one sister, Jo Ann Tritico, as well as nieces and nephews.

By 12, Mr. Hillerman was driving by himself and within a few years, traveling to Dallas and staying alone in hotels to see the opera. But he did not immediately see himself on stage. It was not until he was based in Fort Worth for the Air Force that he decided to audition for a community theater production of “Death of a Salesman.”
“When I stepped on stage, I experienced the greatest high I’ve ever had in my life,” he recounted in a 1987 interview. “And I said to myself, ‘Hillerman, until this moment, you have been bored.’”

Before he left the Air Force, he had worked in nearly two dozen plays. He had found his passion and moved to the East Coast. During 11 years in New York and then four in Washington, Mr. Hillerman appeared in more than 100 roles on stage. But after all those years, he had only $700 in the bank and decided to move to Los Angeles to find better paying work.

He instantly landed a role in a TV movie but struggled for two years after that to find something else. He eventually reconnected with a friend from New York, the director Peter Bogdanovich, who cast Mr. Hillerman in some of his films, including “The Last Picture Show” in 1971 and “Paper Moon” in 1973.

Through the late 1970s, Mr. Hillerman appeared in several sitcoms. He played Simon Brewer, the radio sleuth in “Ellery Queen,” and John Elliot, the sarcastic ex-husband of Betty White in “The Betty White Show.” He also played the role of Mr. Connors, the boss of Ann Romano (played by Bonnie Franklin) on “One Day at a Time.’’

But the role that changed his life came several years later. CBS had cast Mr. Selleck in “Magnum, P.I.” but were not impressed with the English actors who tried out for Higgins. As Mr. Hillerman recounted in 1984, Mr. Selleck’s agent recommended him and he was offered the role two hours after the audition.

“It’s the best gig I’ve ever had,” he said that year. “You’re looking at this rare thing: a happy actor.”