The legendary early firecrackers of rock ‘n’ roll and R&B – Elvis, Little Richard, Jerry Lee Lewis and James Brown – made some of the most joyful sounds of the 20th Century. Yet the music those sounds emerged from – the blues country and gospel – pivoted between joy and despair, ecstasy and adversity. The triumph of kicking hard times in the shins was part of their primal force. Get On Up, the fascinating and convulsive new James Brown biopic starring the extraordinary Chadwick Boseman, is a movie that conducts the crackling electricity of Brown's music with a heat and swagger and verve that rivals the achievement of what Taylor Hackford’s Ray brought off 10 years ago with the life and music of Ray Charles. At the same time, I'm not sure if I've ever seen a Hollywood drama that conveyed such a wrenching sense of the torment that R&B grows out of and transcends.

Born in a shack in the South Carolina woods, then abandoned by his depressed, beaten-down mother (Viola Davis) and abusive father (Lennie James), James, played as a boy by the brothers Jamarion and Jordan Scott, is raised in a whorehouse, where he's baptised in crude sensuality and pain. He is then sent to prison for stealing a suit. When he gets out and starts to perform, trying out those ecstatic wails and the soon-to-be-famous footwork that makes it look like he's dancing on top of boiling water, it's both an attack and an escape: with every last soul scream and rapid-fire shudder-step, he's ascending into the heavens by stomping on his own hidden void.

Boseman gets it all: the yelps and growls and "Huh!"s, the glides and pirouettes and jack-knife splits. But more than that, he gets the delirium, the way that Brown paraded the sonic audacity of funk as a low-down life force. Get On Up captures the radical excitement of an artist who remade the DNA of R&B every time he got up on stage and who presented that sound as raw salvation – his own, and everyone else's.

There's a narrative arc – a mythology, really – that we expect to see in almost any drama about a rock or R&B icon. A young man emerges out of nowhere and parades himself like Dionysius with a beat. He rockets to success, gets high on fame, drugs and his own ego, uses and abuses the people around him and finally takes a fall, which is, perhaps, the start of his redemption. First the urgency of his music redeems everyone who hears it. Then the question becomes: can he redeem himself?

Pain into pleasure

Get On Up delivers on that mythology but pushes it further than almost any previous film has. For this is the story of a man who changes the world with the hard, thrusting defiance of his rhythms, yet draws that music out of so much pent-up fury that he remains, triumphantly and tragically, a tyrant-genius stuck on his own imperious cloud. Boseman, fresh off the wily heroism and impacted anger of his performance as Jackie Robinson in 42, makes Brown a serpentine erotic dervish onstage; offstage he’s a playful and devious sprite who speaks in a mischievous rasp that's part Don Corleone and part pimp. With his regal conked pompadour, insinuating squint and big teeth that look like they want to take a bite out of you, Boseman's Brown is someone you can't take your eyes off of, yet part of the unsweetened authenticity of the movie is that Brown, as portrayed, is such a blazingly self-centred showman that he remains a dictator even for those to whom he's closest.

The director, Tate Taylor (The Help), working from a script by the team of Jez and John-Henry Butterworth, doesn't just employ the usual flashbacks. He leaps around in time and lets Brown gaze into the camera and address the audience, turning the entire movie into a free-form biographical collage, so that we never lose the connection between the exhilaration of Brown's music and the trauma he’s escaping. In one remarkable scene, he has to box, blindfolded, in front of prosperous white men, like the hero of Ralph Ellison's Invisible Man, and right there, out of that insane humiliation, he imagines the members of a ragtime band suddenly getting up and inventing the jabbing catharsis of funk. Could it really have happened that way? Yes or no, it feels poetically right.

Music and myth

Boseman's performance is never less than a virtuoso impersonation – onstage, he simply becomes James Brown – but it's never merely that either. He shows us how Brown's whole life is a performance, a slightly sinister act of hustle and manipulation. The one time he takes off his mask is backstage at the Apollo Theater, when the mother who ditched him suddenly shows up to cash in on his fame. The way Boseman and Davis play this scene is amazing – a tearjerker grounded in rage.

James becomes a kind of monster, trading in women like show horses, beating at least one of them and fining his band members like ungrateful servants; he even insists that they call him "Mr Brown." The James Brown of Get On Up isn't exactly a guy you can cozy up to. He makes the womanising, heroin-addicted Ray Charles of Ray look warm and fuzzy. Yet the movie, without letting Brown off the hook for his behaviour, never loses sight of the glory of his mission: to bring the funk, and to keep heightening it. In the formative days of his stardom, when he's doing songs like I Got You (I Feel Good) in 1965, his rhythms already have a thrust that's spikier, more volcanically charged, than the gliding jubilation of rock. There's a hilarious scene in a recording studio when James is doing Please, Please, Please and an executive complains behind the control-room glass that it isn't a song, because there's no verse, just that one word: "Please!" But one word is all that James needs. He's not telling a story. He's howling – happily – at the moon.

As the film goes on, the funk gets tighter and grander. There's a great scene in which James, at a rehearsal, keeps interrupting the band, ordering them how to play, telling them they don't get it and at first we think he's abusing them, until he starts to explain that every instrument they're playing – guitar, sax, horns – is a drum. Like a space-age Duke Ellington, he has figured out how to turn an entire band into an intricately propulsive rhythm machine. By the time he's performing Get Up (I Feel Like Being a) Sex Machine in Paris in 1971, in wild hair and a leather vest that out-freaks Sly Stone, we can hear the entire universe of black pop encapsulated in this sound: the throttle of '70s funk, the jittery elegance of disco, the sonic boom of hip-hop – it's all right here. Yet at what cost? The double-edged glory of Get On Up is that it lets you revel in the thrilling majesty of James Brown's music even as you're tasting the price that he paid, and made others pay, to create it.          


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