Altman cast her as an Astrodome tour guide Suzanne in “Brewster McCloud,” and her pitch about the art became a part of her character’s dialogue. They continued to work together including two of his best films, “Nashville,” “McCabe and Mrs. Miller,” one of his most intriguingly confounding, “3 Women,” and one of his biggest failures, “Popeye.” Perhaps it was her resemblance to the title character’s leading lady, Olive Oyl, that inspired him to make the film. She said that while some people “intellectualize” about the characters they play, Altman told her to “relax, and you will fall into the role.” He encouraged her to develop her own dialogue for her characters.  Duvall said that it wasn’t until her third film with Altman, “Thieves Like Us,” was shown at the Cannes Film Festival that she realized she wanted a career as an actor. 

Duvall also had iconic roles in Woody Allen’s “Annie Hall” (as the Rolling Stone reporter who said sex with Allen’s character was Kafka-esque and that a rock concert was “transplendent”), and Stanley Kubrick’s “The Shining” (as the wife of a man being consumed by homicidal madness). 

She had a beguiling innocence and naturalism that could contrast with her exaggerated, easily caricatured, appearance. Duvall was not the kind of actress who transformed herself for a role. She made little effort to adopt a different accent or tone of voice, even when playing characters from other countries and centuries. Her interviews, her appearances as herself in the television series she produced, and her performances are seamless. That does not mean she was always herself on screen. It means that she was completely comfortable on screen, finding within herself whatever the character needed. In “3 Women,” for example, based on a dream Altman had, Duvall won the Best Actress award at Cannes for playing Millie, with an impeccably smooth pageboy haircut. Her character babbled on in a manner she intends to come across as confident and sophisticated, but we can see as insecurity and nervousness, while in “Annie Hall,” her journalist character has a lot of confidence, unearned but unquenchable. Both characters are completely believable. Altman said she “was able to swing all sides of the pendulum: charming, silly, sophisticated, pathetic, even beautiful.”

Duvall’s fearlessness made her a match for some of the screen’s most powerful co-stars. Not many performers can appear with Jack Nicholson at his most deranged and Robin Williams at his most cartoonish. She was more than able to hold the audience’s attention. Her Olive Oyl matched Williams’ stylized, cartoonish tone, but her Olive Oyl, was endearing, with her simple, heartfelt song “He Needs Me.”  She is completely natural as a devoted mother acting with then-six-year-old Danny Lloyd in “The Shining.” But there is no image in Hollywood history more iconic than her terrified face as Nicholson uses an ax to smash through the door. She had an exceptional ability, especially for someone so distinctive, to adapt to a stunning range of genres and tones. She acted opposite Monty Python’s Michael Palin in “Time Bandits,” Steve Martin in “Roxanne,” and Sissy Spacek in “3 Women.”