Boyd Holbrook’s Johnny Cash out-cools, out-swaggers and out hell-raises future Nobel Prize winner Bob Dylan in Dylan’s own biopic. I wonder if “A Complete Unknown” director James Mangold ever winced and muttered “Damn” about who he originally cast to star in “Walk the Line?”

Edward Norton’s rendition of folk music legend and activist Pete Seeger is so exacting, earnest and humane as to make one reconsider the lifetime of canny scene-stealing creeps decorating Norton’s resume. It’s a thrilling turn, musically and dramatically, and yes he almost steals the movie.

Monica Barbaro had the unenviable job of recreating a once-in-a-generation voice — Who could? — but her spirited, no-nonsense portrayal pretty much rewrites the book on Joan Baez regarding her relationship with Bob.

But it is Timothée Chalamet who brings the titular “Complete Unknown” to life, who sets the tone for the exacting recreations presented here. Boyish in that “pretty boy of folk” way Dylan was in the early ’60s, tight-lipped and nasal when he sings, a better guitar player than you might realize at first, evasive and elusive as a personality, even Bob himself might mutter “Damn” at how close Chalamet comes to the bone.

Chalamet’s Dylan is a changeling, joker, a musicologist in all but title, a romantic and a romantic poet who dominated the conversation and the pop charts in his prime. It is an unsparingly detailed performance in what was always going to be a frustrating depiction of an artist and his time.

Dylan has cultivated and curated an image as the inscrutable artist, unknowlable in his multitudes, a creator always creating, a “stranger” who only gets stranger with age. Getting to “know” him may have last been possible in about 1963.

“A Complete Unknown” may be a surface gloss tour through the folk 1960s, less gritty than the amusing “Inside Llewyn Davis,” not as revelatory as “I’m Not There,” not as point-by-point detailed as Scorsese’s definitive TV documentary on Dylan, “No Direction Home.” But what a grand gloss it is.

Actors master the guitar and the banjo (Norton) and sing the songs that defined a generation. They’re so good that their singing dominates the screen time in Mangold’s film. Major figures and bit players in the Dylan/Folk Boom ’60s saga pass by in a thrilling blur that perhaps only Dylan aficionadoes will catch.

There’s folk icon Dave Van Ronk (Joe Tippett), giving baby Bob a boost, then straining to keep him on message at the ’65 Newport Folk Festival. Musicologist Alan Lomax (Norbert Leo Butz), whom Dylan tracks down, recognizes as quickly as Pete Seeger and the already-silenced-and-hospitalized-by-Huntington’s Woody Guthrie (Scoot McNairy) just what he’s hearing.

“The future!”

Columbia Records impressario John Hammond (David Alan Basche) and producer Tom Wilson (Eric Berryman) try to shape Dylan’s career and corral his sound in the studio.

Blues legend Sonny Terry, actor/folk-singer Theodore Bikel, folkie Maria Muldaur, guitar icon Mike Bloomfield, they’re all glimpsed in flashes. Is that Mimi Farina (Baez’s singer-sister) sitting next to Bob’s first NYC artist girlfriend, Suze Rotolo (Elle Fanning) at the Newport Festival?

And Charlie Tahan is here to grab guitarist turned one-time Hammond B-3 organist Al Kooper’s moment of immortality, pitching in on “Like a Rolling Stone,” even though — bless his heart — nobody asked him to.

The arc of the story is the one many a biographer and most documentarians have taken with Dylan — his arrival in New York a hitchhiker, hoping to play the folk clubs and track down his idol, Woody Guthrie, that first girlfriend, the first attention, quick rise to fame and the decisive moment when he plugged in, shed the folk troubadour/”protest singer” label and enraged the folk music establishment at the 1965 Newport Folk Festival.

Dylan’s refusal to be pinned-down or categorized, his elusiveness, was the guiding principle of Todd Haynes’ multi-actor recreation of Dylan’s myth, “I’m Not There.” Mangold and co-writer Jay Cocks focus on Dylan’s mercurial reinventions via betrayal.

He abandoned his Jewishness more than once, first when he renamed himself Bob Dylan. He befriended and betrayed his New York activist, college coed, muse and live-in lover (Fanning), the woman (renamed Sylvie Russo here) who gave him his social conscience. He was taken in and mentored by Seeger, Lomax and Van Ronk, and cut them all off the moment he grabbed a Fender Stratocaster.

Dylan fell for folk star Baez, and their torrid affair lit the fuse in his rise to stardom. And when the folk fame grated and the “purity police” of the folk world wanted to pin him down, he dumped her and went on to betray an entire music audience.

It was full and storied life before his mid-60s Triumph motorcycle accident, retreat to Woodstock and return to performing on a never-ending tour. Not bad for a guy whose lone ambition was to be “a musician who eats.”

Chalemet’s Bob has youthful charm and opportunistic guile, and a cynicism born of refusing to be pigeon-holed musically, professionally or romantically.

This performance, more than any other, burnishes the actor’s resume and lets us see the commitment that backs up the potential behind the androgynous sex symbol-driven stardom. Chalamet is so good here one could see him taking his guitar and Greek fisherman’s hat act on the road, Timothée as Young Bob, a troubadour’s musically formative years.

In showcasing so very many songs as they are composed, picked-out, and then raptorously consumed by an eager audience of Baby Boomers, Mangold brings to mind other audiences, the way Dylan’s lyrics are not so much heard, but consumed, savored and judged by the folk audience of the day. That’s much the way rappers speak to a different generaton.

Norton’s Seeger is the conscience of “A Complete Unknown,” a titanic figure rendered in humble, curious and nurturing tones. “A good song can only do good,” he preached to Bob, to blacklisters and to judges who found his political “people power” purity and “communist sympathies” to be unnerving and “anti-American.”

Holbrook’s Cash shows up as middle-America’s validation of the new singer/songwriter/gunslinger in town, funny and tipsy and cocky and a bigger influence on Dylan than we realized at the time.

Chalamet’s Bob lets us see that while he stole his songs from everyone and everywhere — borrowing rivals’ arrangements of folk classics, writing new songs on older melodies — he stole his smoking style from James Dean, his cool from McQueen and his wardrobe and shades from The Man in Black.

And Fanning’s front-and-center portrayal of that early muse is luminescent. Sylvia/Suze is a sort of EveryBoomer (she and Bob and Joan were born pre-Baby Boom), a child raised in one world ready to remake it into something new, an early devotee of a Great Cause, crushed when it turns out her genius idol-boyfriend is growing beyond her and her fellow devotees, moving on to greater things.

The music, from the humming streets of 1961 Greenwich Village to the clubs and churches, festivals, recording studios and intimate “Here’s a song I’m writing” or “Hey Woody Guthrie, I wrote you a song” moments may label “A Complete Unknown” as a superficial treatment of the Dylan legend. But in focusing on the tunes and the lyrics, Mangold makes us reconsider the head-snapping surprise of that Nobel Prize in Literature.

The songs are the soundtrack of this saga of a life. The tunes are the melodies and ethos of their hopeful but politically-roiled age. And the lyrics take us deeper into Dylan than any biography, in book or big screen form, ever could hope to go.

Rating: R, profanity, smoking, mild violence

Cast: Timothée Chalamet, Elle Fanning, Edward Norton, Monica Barbaro, Dan Fogler, Charlie Tahan, Joe Tippett, Scoot McNairy and Boyd Holbrook

Credits: Directed by James Mangold, scripted by James Mangold and Jay Cocks, based on the biography by Elijah Wald. A Searchlight release.

Running time: 2:21