She was 87. The cause was not immediately known, said Francesca James, a longtime friend who was with her when she died.

Ms. Harris had a lengthy, overstuffed résumé as an actress, with dozens of movie and television credits, including the 1955 film adaptation of John Steinbeck's novel of brotherly rivalry, "East of Eden," in which she played the girl who falls for the tormented younger sibling played by James Dean, and nearly eight years in the 1980s as an eccentric country singer on the prime time soap opera "Knots Landing." But perhaps more than any other performer of her era and her elevated stature, she owed her stardom and reputation to the stage.

Sometimes called the first lady of the American theater, she made her first Broadway appearance while she was still in college, and over the next half century-plus earned 10 Tony nominations, more than any other performer. The last was in 1997 for a revival of "The Gin Game," D. L. Coburn's mordant comedy about the contentious friendship between two isolated denizens of an old age home that emerges over a card table. She didn't win, though she'd been there and done that five times, the first performer to be so honored so often. Angela Lansbury and Audra McDonald have since matched this total, but in 2002, Ms. Harris won for the sixth time, a special Tony for lifetime achievement, putting her in a class by herself.

She was, if such a thing is possible, born to act. As a girl she declared to a high school drama teacher, "Acting is my life," and she was once described by the director and critic Harold Clurman as "totally designed to be a good instrument on the stage." Slim, red-haired, physically graceful though not especially athletic, she had the aura of delicacy but was not a mesmerizing beauty; nor was she a distinctive, public personality. In interviews, she was unremittingly humble, dwelling on what she deemed her failures far more than her successes and speaking of acting as an imperfectible craft for which the effort at rendering a character, not the finished result or the applause, is not only the challenge but the reward.

"Acting is always an adventure, and a struggle, and a quest to find the truth," she said. On another occasion, more than 30 years after her career began, she allowed that the work of an actor still had the capacity to frighten her.

"It's wanting to do it right, that's where the fear comes in, but who can say what's right?" she said, adding: "We're very delicate creatures, aren't we?"

Celebrated as she was, she was more artist than star, rarely associated with a long-running hit; only 6 of her more than 30 Broadway shows ran as long as six months. Renowned for her wide range and her dedication to each performance, even — or maybe especially — in plays that critics and audiences found wanting, she became a compelling figure by stepping into a role, the proverbial vessel filled by whatever character she had undertaken to play. The playwright John van Druten, who adapted Christopher Isherwood's novel "Goodbye to Berlin" into the play "I Am a Camera," the show that made Ms. Harris a star in 1952 (and later became the source material for the musical "Cabaret"), referred to her in a 1955 interview with The New York Times Magazine, as a glass pitcher.

"You pour in red wine, the pitcher looks red; pour in crème de menthe, it is green," van Druten said. "When she's by herself, Julie's almost transparent, almost nonexistent."

Ms. Harris made herself known in 1950 as a 24-year-old playing a 12-year-old, the loquacious, motherless, fiercely self-tormenting Frankie Addams, in Carson McCullers's adaptation of her own novel, "The Member of the Wedding." With her hair cut tomboy short, she spent virtually all of the play onstage, dreaming aloud, remonstrating with the sage family cook Berenice (played by Ethel Waters), hectoring her young cousin John Henry (Brandon De Wilde) and berating herself with the incessant needy bleat of loneliness. It required a huge effort, and Ms. Harris received the kind of notices that can — and in this case did — propel a career.