Mercurial, menacing, charismatic and deep — those are the traits that made Don Cheadle the right guy to take on mythic jazzman and icon of cool Miles Davis.

Cheadle suggests, in not-quite-equal measure, each of those facets of persona in “Miles Ahead,” a musical bio-pic that takes its title from a 1950s breakout LP by Davis. But a better title might have been “Sketches of Miles,” as Cheadle, who co-wrote the script and directed the film, is more interested in the mythic Miles, the musically-blocked, drug-addled paranoid of the late 70s, a man trapped by his “never repeat yourself” ethos and the fear he’ll never top his seminal work, also from the ’50s, “Sketches of Spain.”

The fictional story that makes up this portrait is a gonzo, guns, girls and drug-fueled couple of days when a would-be Rolling Stone writer (Ewan McGregor) shows up to write Miles’ “comeback story” and is eyewitness to the magic of Miles and the madness of Miles.

Cheadle’s Davis is never without a smoke, rarely without a gun, living in the Manhattan dark with his cocaine, his “brown liquor,” his ego (“I was born modal.”) and his tapes.

That’s where the Scottish Dave (McGregor) finds him. He wants that Great Black Whale of music journalism — a Miles Davis interview.

“If you gon’tell a story,” Davis hisses, “come with some ATTITUDE…Don’t be corny.”
And as conventional as “Miles Ahead”, with its “a revealing day-in-the-life” structure, is, one thing you can never call it is “corny.”

There’s a larger frame, a late-career documentary interview, that the film exists within. The Rolling Stone encounter — totally fictional — is a standard bio-pic device. Have somebody there to witness the greatness at a pivotal moment.

Because Miles is in crisis. He’s alone, flashing back to his great romance, Frances (Emayatzy Corinealdi, enchanting), the dancer who got away, and determined not to let his latest session tapes fall into the hands of Columbia, his record company.

Dave shows up at Miles’ door, takes a punch in the mouth, shrugs off having a gun pulled him and we’re off. Miles needs money from Columbia, so Dave will drive. Miles needs drugs, so Dave will use that as an entre to Miles’ confidence.

In a world where artists have been known to take things to extremes, Davis isn’t shy about pulling a pistol on manipulative record execs, unscrupulous promoter/producers (Michael Stahlbarg) and anybody else who crosses him. The clever touch is having this machismo blow up in Miles’ face, time and again.

Flashbacks show us his womanizing (writing his number on a $20 bill), his hipster appeal and his genius — on stage or in the studio. A 1950s encounter with a cop shows the racism that helped drive his bitterness.

“Just woke-up black.”

In the film’s present, Cheadle/Davis broods. And fumes. The script is hard-pressed to not drop “mother-f—–” into Miles’ every line, often to comic effect.

But the real comedy comes from McGregor’s Dave, tricking Davis, turning the tables on him, whispering his story notes into a clunky tape recorder, a corduroy sports coat cliche of the unscrupulous Brit-trained reporter.

“Jazz’s Howard Hughes, revealed and REVILED.”

Davis eschews the “jazz” label. “Call it social music.” But as he and Dave bond over drugs, a shared love of ’70s hair and oversized sunglasses, we get a picture of the artist that was, a legend trying to live up to that legend.

“Miles Ahead” is a performance showcase, and might have seemed like a sure Oscar nomination for Cheadle, on paper, had the picture been more complete, more fulfilling. It suffers in comparison to Ethan Hawke’s Chet Baker biography, “Shades of Blue.” But not by much. Movie fans will recognize the predatory music industry “types.” Jazz fans will spot the figures of collaborators Bill Evans, John Coltrane and Herbie Hancock, played by actors, onstage with Miles at various points.

And Cheadle fans will marvel at the convincingly-mimicked horn playing, the care he put into this interpretation, getting across not just the abrasive personality but the magnetic charm and on-stage sensitivity that made Miles Davis, from the 1950s on, “Miles Ahead.”

MPAA Rating:R for strong language throughout, drug use, some sexuality/nudity and brief violence

Cast: Don Cheadle, Ewan McGregor, Emayatzy Corinealdi Michael Stuhlbarg
Credits: Directed by Don Cheadle, script by Steven Baigelmanand Don Cheadle. A Sony Classics release.

Running time: 1:40