Born in Texas, Duvall was discovered by Altman, who was impressed by her upbeat presence and cast her in the black comedy film Brewster McCloud (1970).

[10] Growing up, Duvall's only exposure to acting was when she forgot her lines to Joyce Kilmer's poem "Trees" in a sixth-grade talent show.

[6] After graduating from Waltrip High School in 1967,[11] she sold cosmetics at Foley's, a department store; she attended South Texas Junior College and majored in nutrition and diet therapy.

On April Fool's Day 1970, Duvall was hosting a party in Houston for her artist boyfriend, Bernard Sampson, when three crew members in town for Brewster McCloud (1970) pre-production arrived.

"[19] Duvall had her breakthrough for playing a spaced-out groupie in Altman's 1975 ensemble comedy Nashville,[20] which was a critical and commercial success.

Keith Carradine, who collaborated with Duvall on Thieves Like Us and Nashville, told Variety: "She had that fascinating physical appearance, there was something slightly off-center and hauntingly beautiful about her.

In 1977, Duvall gave what some critics considered to be one of her best performances in Altman's psychological thriller 3 Women, portraying Mildred "Millie" Lammoreaux, a woman living in a dreary California desert town.

[26] Texas Monthly critics Marie Brenner and Jesse Kornbluth praised Duvall for giving an "extraordinary performance".

[27] Michael Sragow of The New Yorker called her "brilliant: she coins a brand-new caricature of the confident yet clueless single female, then suggests a real person underneath.

"[42] In a 2021 interview with The Hollywood Reporter, Duvall spoke openly of the emotional toll of the role and the challenges of long days on the set, but said that Kubrick was "very warm and friendly" to her.

[45][46] Anne Billson of The Guardian stated that "Duvall's horrified reactions as her husband reveals himself to be a mortal threat provide the film with many of its iconic moments.

"[47] Bilge Ebiri of Vulture wrote: "Looking into Duvall's huge eyes from the front row of a theater, I found myself riveted by a very poignant form of fear.

"[48] Jessica Jalali of Screen Rant ranked it the best performance of her career, calling her "the heart of the film; she is out of her depth in dealing with her husband's looming insanity while trying to protect her young son, all while being fearful of the malevolence around her".

"[50] While Duvall was in London shooting The Shining, Robert Altman cast her to portray Olive Oyl in his big-screen adaptation of Popeye, opposite Robin Williams.

She starred in seven episodes of the series; "Rumpelstiltskin" (1982), "Rapunzel" (1983), "The Nightingale" (1983), "Snow White and the Seven Dwarfs" (1984), "Puss in Boots" (1985), and "Aladdin and His Wonderful Lamp" (1986).

She created Nightmare Classics (1989), a third Showtime anthology series, which featured adaptations of well-known horror stories by authors including Edgar Allan Poe.

[69] She next appeared as the vain, over-friendly, but harmless Countess Gemini—sister to the calculating Gilbert Osmond (John Malkovich)—in Jane Campion's 1996 adaptation of the Henry James novel The Portrait of a Lady.

[70] In 1997, she played a beatific nun in the comedy film Changing Habits[71] and a besotted, murderous, ostrich-farm owner in Guy Maddin's fourth feature Twilight of the Ice Nymphs.

[72] In the same year, she played Chris Cooper's character's gullible wife who yearns for a better life in Horton Foote's made-for-television film, Alone.

In the 2000s, Duvall accepted minor roles, including as the mother of Matthew Lawrence's character in the horror-comedy Boltneck (2000) and as Haylie Duff's aunt in the independent family film Dreams in the Attic, which was sold to the Disney Channel but was never released.

[76] After a small role in the 2002 independent film Manna from Heaven, Duvall took an extended hiatus from acting and public life.

[79] After a 20-year absence, it was announced in October 2022 that Duvall would be acting in The Forest Hills, an independent horror-thriller film directed and written by Scott Goldberg.

[95] After the 1994 Northridge earthquake, Duvall and Gilroy moved from Benedict Canyon in Los Angeles to Blanco, southwest of Austin, Texas.

[2] In 2021, Seth Abramovitch, writer for The Hollywood Reporter, found Duvall for an interview saying, "I only knew that it didn't feel right for McGraw's insensitive sideshow to be the final word on her legacy.

[104] After several months in hospice care, Duvall died due to complications from diabetes at her home in Blanco, on July 11, 2024 a few days after celebrating her 75th birthday.

[113] MovieWeb ranked Duvall as the fifth-best scream queen of all time, writing that her performance in The Shining was "a thing of glory".

[116] Peter Bradshaw of The Guardian described her as "unique and often misunderstood" and said she "was intensely modern, the very face of the New American Cinema, but was also in her slender grace and wide-eyed charm, and her way with a cigarette, a neo-flapper, a kind of 20s or 30s woman reborn long after the second world war which also made her an excellent casting choice in period movies.

"[117] The New York Times called her a "fixture" of Hollywood,[7] and wrote: "With her gossamer frame and toothy smile, she was one of the biggest film stars of the 1970s.

[120] Jamie Lee Curtis cited Duvall as an influence, writing: "She showed that you could change and grow and develop and, of course, now we see so many wonderful actresses and actors become producers and directors and creators.

"[122] Others who have praised her work in tributes include Woody Allen, Mia Farrow, Daryl Hannah, Michael Palin, Malcolm McDowell, and Paul Simon.