Robert Altman, the influential director of "M*A*S*H" and "The Player" who was known for his groundbreaking naturalistic films full of overlapping dialogue and unrivaled ensemble casts, died Monday evening at 81 years old. The cause of death was complications due to cancer, his production company announced Tuesday (November 21).

Especially revered by actors and critics in his 50-plus-year film career, Altman famously encouraged improvisation from all his actors -- a group that featured everyone from Warren Beatty to Lindsay Lohan -- dating back to the film that first made him a director to be reckoned with, the anti-war black comedy "M*A*S*H," which was released in 1970.

"A great man has left this stage," John C. Reilly, who had recently worked with Altman on "A Prairie Home Companion," told MTV News. "If Bob had his way, I'm sure he would want the speeches about him to be short and to the point. In my too brief time with him, his life seemed to be concerned with two things: telling it like it is and having fun."

The consummate actor's director, Altman's name has become associated with a very specific type of film in recent years. An "Altman-esque" film is recognized to be a movie that champions the hallmarks of his work -- jaw-dropping casts, intersecting story lines and long tracking shots.

Born in Kansas City, Missouri -- "Kansas City" was the title of one of his later works -- in 1925, Altman was educated in Catholic schools and a military academy. He enlisted in the armed services at a very young age, flying B-24 bombers during World War II. He was later discharged. Once he settled in Los Angeles, the future filmmaking icon labored to find footing in the industry he would later become synonymous with, working as an extra, writer and director of industrial films.

Finally, with the success of "M*A*S*H," Altman was well on his way to establishing his unique style and anti-Hollywood predilection for subject matter. Triumphs like "McCabe & Mrs. Miller" (1971), the sprawling "Nashville" (1975) and the Hollywood satire "The Player" (1992) were interrupted by critical and box-office fiascos like 1980's "Popeye" and 1998's "The Gingerbread Man." Such was the nature of Altman's work, confounding expectations and never taking the sure and easy path. It comes as no surprise that he would experience markedly strong highs and lows in his career.

Nominated for five Academy Awards, Altman only just received his first Oscar in March in recognition of his lifetime of work. The award, felt by many in the industry to be long overdue, was delivered to him by Meryl Streep and Lily Tomlin, who introduced him in quintessential Altman style, talking over each other repeatedly. The Oscar represented a significant moment for the maverick director, proving once and for all that though he may have worked on the fringes of Hollywood, he was appreciated by the establishment at last.

It was during his speech at the Oscars that Altman first publicly revealed that he had received a heart transplant a decade earlier. The news caught many by surprise since the filmmaker's output was as prolific as ever, and he directed such films as "Gosford Park" (which earned six Oscar nods) and "The Company" in recent years.

In May, Altman's last film, "A Prairie Home Companion," was released to stellar reviews (see [article id="1528557"]"Lindsay's Laundry List: 'SNL,' Trip To Kenya, Two More Movies"[/article]) Sporting the now-expected stellar ensemble cast of veterans like Streep and Kevin Kline, alongside newcomers like Lindsay Lohan, the film was one of the director's greatest triumphs in recent years.

At the time of his death, Altman reportedly had been nearing the start of production on another film based on the documentary "Hands on a Hard Body." Just days before his passing, John C. Reilly said in a separate interview that he was likely joining that production -- not an unusual occurrence, considering Altman's practice of using the same actors in many of his films.

"A Prairie Home Companion" now stands as his last contribution to the field Altman devoted his life to. As it turns out, the film was interpreted by many to be a meditation on death, a theory Altman acknowledged in May. Subsequent to the news of his death, Reilly told MTV, "I guess I'll see him in the next reel, as he used to say."

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