Chadwick Boseman brings the funk as James Brown in Get On Up

Chadwick Boseman surpasses all expectations as the legendary (and not a little notorious) superstar James Brown in Tate Taylor’s biographical drama Get on Up. Boseman’s got the look, the attitude, the moves – no small feat – and the voice. He even sweats like James Brown.

Boseman’s stellar performance is not enough, however, to overlook how messy the rest of the film is. Adopting a structure (very) heavy on flashbacks – and flashbacks within flashbacks – Get on Up falls prey to the same drawbacks that befell Ray (2004) and Walk the Line (2005). Regardless of the Oscars those films were nominated for – and in the case of actors Jamie Foxx and Reese Witherspoon, won – both films had a maddening tendency to overlook or even ignore certain facts. So it is with Get on Up, which affords the Godfather of Soul the respect he certainly deserves, but not the comprehensiveness his story demands.

The future Hardest Working Man in Show Business grew up poor in rural Georgia, abandoned by his parents (Viola Davis and Lennie James) and looked after by the neighborhood madam (Octavia Spencer). He discovered his “groove” early but got into trouble from time to time, until teaming with Bobby Byrd (Nelsan Ellis of “True Blood”) and forming a rhythm-and-blues group that fast-tracked him to worldwide stardom.

Back and forth the narrative goes, succeeding less in conveying Brown’s story than continually undercutting dramatic momentum. The sequences of Bozeman as Brown strutting his stuff are competently handled by Taylor – with the actor adding a little something extra.

Ellis is first-rate as the loyal but long-suffering bandmate, and Dan Aykroyd enjoys his best role in a long while as record executive Ben “Pop” Bart, who makes Brown a success then comes along for the ride. (Trivia buffs will note with amusement that Aykroyd worked with Brown multiple times, including Doctor Detroit and The Blues Brothers.)

Davis, who earned an Oscar nomination for Taylor’s overrated 2011 adaptation of The Help, has only a handful of scenes as the wayward mother who comes back into her son’s life too late, while James and Spencer (who copped an Oscar for The Help) are given very short shrift – which proves indicative of the film as a whole.

Brown’s wives and children are introduced, then summarily dismissed. There’s no mention of his illegitimate children, or of third wife Adrienne Rodriguez, who died in 1996 and whose marriage to Brown was rife with allegations of spousal abuse. Brown’s tax problems are mentioned briefly, then forgotten. Although the film dutifully covers the drug-fueled, high-speed police chase in 1988 that landed him in jail, the narrative simply jumps forward to 1993 as he prepares for a concert.

These failings do not reflect at all on Boseman’s charismatic performance. Occasionally addressing the audience directly – a technique recently used in Jersey Boys – Boseman’s James Brown is a vivid characterization. He’s charismatic, flamboyant and unexpectedly generous, yet equally capable of sudden anger and unexpected cruelty. He’s a man of tremendous ego, yet the insecurities are always there, just underneath the surface. Not unlike the showman he’s portraying, Boseman gives everything he’s got – and then some.

Get on Up opens Friday