A 1979 file photo of director Robert Altman. (Los Angeles Times / November 21, 2006)

Robert Altman's films were audacious. He expanded the boundaries of genres. He gave his actors freedom to improvise and over the years created a stock company of stars. Along the way, he often polarized critics and audiences — and drove studio heads crazy.

Not every film he did was a masterpiece, and he had lulls in his career. But Altman was nothing if not resilient, and just when Hollywood had written him off, he would make a dazzling comeback.

His experimental style, known for overlapping dialogue and loosely structured stories, has influenced contemporary directors such as Paul Thomas Anderson, who was the standby director on the then-ailing Altman's final film, 2006's "A Prairie Home Companion." Altman died at 81 a few months after the ensemble comedy was released.

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So it's fitting at UCLA Film & Television Archive's "Robert Altman: A Retrospective," which opens Friday at the Billy Wilder Theater, is a portrait of an artist not only as a young man but as a lion in winter. It's a comprehensive look at the maverick director's expansive body of work that continued for more than half a century.

"I consider him to be the American director of my generation," said Elliott Gould, who worked with Altman several times, most notably on 1970's "MASH," in which he played Trapper John, 1973's film noir "The Long Goodbye" as L.A. shamus Philip Marlowe and 1974's "California Split."

The series, which continues through June 29, includes Altman's classic films including "MASH," 1975's "Nashville," 1992's "The Player," 1993's "Short Cuts" and  2001's "Gosford Park," as well as rarely seen works, including early industrial films, episodic TV work and even a 1965 comedic short "Pot Au Feu," in which he also appears, that extols the virtues and joys of weed.

He was an actor's director — and they loved him for it.

"It turned out he was like my father, giving me so much opportunity, so much space and room to invent," said Gould.

"He's the only reason I'm in the business," said Tom Skerritt, who appeared in "MASH" and 1974's "Thieves Like Us."

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Shannon Kelley, head of public programs for the UCLA archive, noted that Altman was "modest about the depth of intelligence that it took to make films his way. He always gave credit to actors more than anybody. Once he had cast his film, [he felt] his creative role was finished and he was just there to witness what these actors were doing."

Several of the actors who worked with Altman will be appearing at the screenings, including Gould and Skerritt.

Gould recalled first talking with Altman about playing the role of Duke Forrest for "MASH" — a role Skerritt ended up playing. Gould didn't know if he could make that Southern character believable and voiced his preference for Trapper John, who was from New England. He told Altman: "I have the spirit and the heart for it."

And Altman agreed.

"It is like Bob let me cast myself, and that was the beginning of our work," recalled Gould.

But they had a rocky relationship at the outset because Gould was uncomfortable with Altman's freewheeling style. "By the time we got to 'California Split,' I knew exactly where his mind was all the time."

Perhaps their finest work together was on "The Long Goodbye," Altman's unique take on the classic Raymond Chandler detective novel. "We broke the mold," said Gould. "It's like an American jazz piece. I was so privileged and blessed to be able to do some more substantial work with him."

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The majority of the films in the retrospective were donated to the archive by the Altman estate a few years after his death.