Photo: Dave Franco (left) and brother James Franco (right) in their new movie ‘The Disaster Artist’

How do you tell the story of the “best worst film of all time” without getting lost in the meta aspects of the production? Things can go horribly wrong when good actors try to be bad – which is much like great sports teams playing down to the level of their competition, right?

That’s one of the first issues that comes to mind watching James Franco during the early minutes of “The Disaster Artist,” the new film he not only acts in, but produces and directs. The reputed renaissance man has been known, over the last decade or so, for diving wholeheartedly into diverse ventures – master’s degree programs, soap operas, multi-hyphenate opportunities behind the camera – with a degree of abandon that borders on the ridiculous.

What’s this guy trying to prove?

Curiosity, perhaps. Commitment, even despite his having a restless soul at a time when it makes the most sense for him to take risks. These are traits that can be difficult to accept and relate to, especially when most of us pursue far more focused, single-minded lives and careers.

What do we know of such passion?

That, to some extent, seems to be the point of “The Disaster Artist.” On its most basic level, it questions the drive and identity of Tommy Wiseau (James Franco), the would-be actor and director who teamed up with his friend and fellow struggling actor Greg Sestero (Dave Franco) to make a movie – “The Room” – which would become a cult sensation due to its sheer inanity. Tommy, an enigmatic figure with a muddled indiscriminate accent, no recognizable talent either in front of or behind the camera, and a perplexing lack of concern for how others saw him, walked through life without limits, able to do whatever struck his fancy, but there was a peculiar disconnect – a social and cultural chasm that separated him from the regular flow of life.

When he meets up with Greg in an acting class, Tommy’s reckless abandon strikes a nerve with Greg, who recognizes Tommy’s freedom and desires some of that for himself. Tommy is able to do anything, so when he offers the chance for the pair to head off to Hollywood to try their luck on the biggest stage, Greg leaps, placing full faith in Tommy. And when, after spending time seeking to land agents and small gigs, Tommy pitches making a film on their own, again Greg, like Wile E. Coyote, races off the cliff in pursuit of Tommy’s Road Runner.

For James Franco, the move to play Tommy is far more than Franco just being his rather mercurial self. He and longtime friend (and producing partner) Seth Rogen sought the rights to Greg Sestero’s book (The Disaster Artist: My Life Inside The Room, the Greatest Bad Movie Ever Made) and recruited screenwriters Scott Neustadter and Michael Weber (“500 Days of Summer” & “The Fault in Our Stars”) to explore something more than the frenzied fun of a behind-the-scenes disaster in the making. The book’s chapters alternate between the chaos of filming and the evolving relationship dynamic between Greg and Tommy. The film jettisons many of the production aspects of the narrative, placing a premium on the developing bromance, which suffers through the typical ups and downs one might expect under ordinary circumstances.

The beautiful discovery here arises from the casting of the Brothers Franco, who have an obvious sibling affection and low-simmering rivalry that informs the friction that emerges both onset, later in the production, and when Greg starts to accept other opportunities during the final stages of the filming of “The Room.”

It is easy to forget that we’re watching the making of a horrible film – see Tim Burton’s “Ed Wood” or Frank Oz’s “Bowfinger” for great examples of that distinct genre – because what Franco gives us is a master class in the art of sibling pairings, which could be a subdivided genre all its own (think Casey Affleck in front of the camera and brother Ben behind the scenes on “Gone Baby Gone” for a recent and quite brilliant installment). He and younger brother Dave, a rising star on his own with franchises like “Neighbors” and “Now You See Me” in his filmography, reveal a shared camaraderie full of the intimate push and pull they likely perfected as kids.

But James, pulling primary double duty, heads off into rare territory on his own though. Watching him live in the alternative skin (and long hair) of Tommy feels reminiscent of the impossibly Method-driven performance of Jim Carrey as Andy Kaufman in “Man on the Moon.” A new Netflix documentary “Jim & Andy: The Great Beyond” illustrates the otherworldly and personality fracturing effort of Carrey to pull the spirit of Kaufman and his great creation, Tony Clifton, back from the dead.

There’s never the sense that Franco goes to that extreme with Tommy Wiseau, but what he does is far more than mere mimicry or imitation. He leaves flattery behind and finds the authenticity of this man, pointing the way to a real shot at critical redemption for Wiseau and “The Room.”

Rating: R; Grade: A