Michael Mann’s 1992 colonial epic “The Last of the Mohicans” will be celebrating its 20th anniversary this year, if you can believe it. The film — an adaptation of James Fenimore Cooper’s novel — has remained a highly regarded effort in the director’s filmography, which mostly consists of modern urban yarns concerned with the law and order imposed by man.

But it’s the law and order of nature — as it gives way to the impositions of occupiers — that largely governs the tone and atmosphere of his fourth feature. The film is unique in Mann’s canon for its period trappings, but of a piece with his penchant for deep emotional currents that announce themselves only in the nuance of performance.

Indeed, it is still the film’s sweeping romance, its epic sadness, its viscous sense of honor that resonates emotionally to this day.

Mann has tinkered over the years with his preferred version of the film. The first cut he assembled for Fox in 1992 was around the three-hour mark and necessitated considerable trimming for commercial purposes. The DVD release was touted as an “expanded director’s cut” but featured only minor additions throughout the film. Finally the Blu-ray release in the fall of 2010 was stamped as “definitive,” the director’s final say. Again the nuance of the assemblage was tweaked.

In honor of the film’s 20th anniversary, the American Cinemateque premiered the DCP of that cut at the Egyptian Theatre in Hollywood Friday night. Mann was on hand for a Q&A session following the screening and he reflected on how his evolution as a filmmaker informed the nips and tucks along the way.

“I understand story better [now],” he told the LA Times’ Geoff Boucher, who moderated the session. “When I was doing the original in 1992, I wanted to jam or insert the audience into the narrative so that things would just happen and you kind of tried to find out where I am in context, kind of inductively. And that wasn’t really serving the story. There’s a hopefully much clearer path in this version. The story is presented in a more deductive way.”

Given the way he talks about it, one might think the alterations have been drastic over the years, but really they’ve been more about the minutiae and essence of things than anything else. Naturally a filmmaker like Mann, obsessive with the details of his productions (going so far as to craft dense backstory for his characters, catnip for actors), would want to peel back such subtle narrative layers.

Mann first saw the most famous previous version of the story, George B. Seitz’s 1936 production, when he was three or four years old. It had a lasting impression on him, he said, because of two fragmented ideas that had bounced around inside his head ever since.

“[There was] something to do with this corollary tragedy, that was very sad, of a suicide, which of course I was recalling Alice and Cora,” he said. “And there was something about the anomaly of Indians who didn’t look like how I recalled Indians looking for movies, because of course they were Northeastern woodlands Indians — they were Iroquois — in conjunction not with cowboys but with red coats. So something just stuck.”

Trying to figure out what production he wanted to mount in 1991, which was five years removed from his last theatrical feature (he had been working in television consistently at this time), he suddenly remembered these remnants of the story. He went to Fox brass and set about carving a new film out of the novel.

The production was a physically grueling one. “Everybody was in the best shape of their lives,” Mann joked. Hiking 45 minutes up the mountains of North Carolina Appalachia, the cast and crew all pitched in to transport equipment and reach the breathtaking locations that are key to the film’s identity. Additionally, a fully functioning, three-sided recreation of Fort William Henry was a gigantic undertaking. The whole production, Mann said, was a “massive operation.”

Nevertheless, he quipped that he probably had a more difficult time adapting what is notorious for being a poor piece of literature.

“It’s not a very good book,” he said. “James Fenimore Cooper had vast real estate holdings in 1825 when he wrote the book. So the novel is almost a justification for a massive land grab…that the Euro-Americans will be a better steward of the riches that God bestowed upon American Indians. And that, of course, was not the perspective of American Indians. So the revision of history was one of the things I didn’t care for in the novel.

“What really saved us was [Louise-Antoine,] Comte de Bougainville — who later goes to Hawaii and discovers Bougainvillea, which we have all over Los Angeles — he wrote a diary of every single day of that whole campaign. And the diary reads — it’s ironic, it’s funny, it’s sarcastic, it’s fantastic. But it literally told us what happened every single day of August 1757.”

Such scholarly asides are typical in a discussion with Michael Mann. A simple question yields a bounty of information, as if unlocking the door to a closet packed with ideas waiting to tumble out. He’s meticulous, and it’s not an affectation. (Mann is, to this day, the only person I’ve ever interviewed who pulled out his own recorder to document the session.)

On one hand he’ll discuss the arrangement of Dougie MacLean’s modern folksong “The Gael” for the score and implementing a “shameless imitation” of Arvo Pärt’s “Perpetuum Mobile” (a piece of music, he educates, that never resolves back into its time), while on the other hand offering that his Cora Munro was listening to Handel’s “Messiah” in her upwardly mobile neighborhood of Portman Square back home in London two years before she made the journey to the new world in 1755 (an entirely manifested level of insight into the character).

That attention to detail also tends to stretch to the physicality of a given production. Mann concocted a regimen to transform actor Will Smith into heavyweight fighter Mohammed Ali for the 2001 film “Ali” that has become the stuff of legend. The blockbuster star hit the weights and the ring but also ran in boots through snow, all in all clocking in six hours of training per day, five days a week.

Daniel Day-Lewis, meanwhile, is an actor famous for his commitment to a role. His preparation and method are a trademark, making him a star more than worthy of the two Oscars for Best Actor he’s acquired over his career. It’s a director-actor match made in heaven.

“Daniel is athletic as a long-distance runner,” Mann recalled of his leading man. “He’ll get up in the morning and do 10, 15, 16 miles. But he had no upper body development, and so he took six, seven months to put on all that weight. And the ambition for Daniel and myself was to have him acquire all the skill sets that Daniel Boone would have had.

“Daniel Boone could leave a populated area and spend two years in the wilderness, eat three meals a day and live. These were all techniques learned from the American Indians. So the idea was, which I firmly believe, if an actor can actually do the things of the person he’s portraying, he truly becomes that person. You do it, you own it…As a director, that’s what you want. I’m interested in actors and actresses who are for real, who are adventurous, who are very ambitious, who see it as an adventure and are ready to kind of commit, not out of discipline or coercion but out of, ‘Why would you want to do it any other way?’ Who wouldn’t want to do it if you could?”

That incessant curiosity and longing for experience is what drives Mann as a person, and it’s what fuels the textual authenticity of his work as a filmmaker. Complexity is what satisfies him, and one need look no further than the shading of the villain at the center of “The Last of the Mohicans” for evidence of that.

“Magua is a wonderfully complex character,” Mann said of the Mohawk-adopted Huron antagonist, amid discussion of the film’s emotional finale. “He happens to be the only one who probably analyzes the politics. The American Indians are in an existential crisis…Magua’s analysis, which he presents to General Montcalm and then again to the tribunal, is astute. He’s not foretelling Indian gaming but he could be foretelling Indian gaming.

“It’s the duality of him as both the antagonist and also as a person we understand because of his own personal tragedy. And also his perspective is more current. So the moment when he softens when Alice is on the ledge, and how and why she arrived at that particular moment and the loss that everybody shares at the end looking into the frontier, the mountain range — the frontier is this moving zone of what’s coming next — that’s some of what’s resonating. That’s what was important to me directing this film. And Wes Studi, by the way, was just marvelous. That moment, it’s all right there in his face.”

Indeed, three names in the opening credits sequence drew applause from the audience Friday night. The first, of course, was Michael Mann. The other two were cinematographer Dante Spinotti and actor Wes Studi, whose performance as Mogwa is easily one of the best Mann has ever directed.

Somehow “The Last of the Mohicans” was all but ignored by the Academy, despite a September release and a favorable reaction. It was only nominated for one Oscar, Best Sound, which it won.

BAFTA was more welcoming, handing Spinotti an award for his lensing and makeup artist Peter Robb-King another for the indigenous detail, as well as nominations for Best Costume Design, Best Original Film Score (which wouldn’t have flown with the Academy given the sampling), Best Production Design, Best Sound and Best Actor (Day-Lewis, who won the London film critics prize for British Actor of the Year and was three years removed from a Best Actor Oscar for “My Left Foot”). Meanwhile, the American Society of Cinematographers saw fit to nominate Spinotti’s work, as did the American Cinema Editors for cutters Dov Hoenig and Arthur Schmidt.

Along with “Heat” and “The Insider,” I find “The Last of the Mohicans” to be in the top tier of Mann’s filmography (his best work, therefore, coming in the 1990s). And it still packs a wallop, refined in its thematic structure, affecting for its deep sense of longing and pent-up passion.

Believe it or not, the above only scratches the surface of the discussion, really. So provided below is the full Q&A session with Boucher, covering other topics such as Mann’s affinity for personal political hero Russell Means, who stars as the titular character of the film, training and categorical details of the vast amount of extras on the production and other historical influences (like the work of artist Benjamin West) that had a hand in his vision of “The Last of the Mohicans.” Give it a listen below, and here’s to a happy 20th for an gem of its time.