A detonation of pure acting firepower is what’s on offer in this movie version of August Wilson’s 1982 stage play. Declarative and theatrical it might be, but it’s also ferociously intelligent and violently focused, an opera of passion and pain. We see African-American musicians hanging around a white-owned Chicago studio one stiflingly hot day in the 1920s, waiting for the legendary blues singer Gertrude “Ma” Rainey to show up with her entourage so they can cut an album. The lead track is expected to be her live hit, Ma Rainey’s Black Bottom, and the drama imagines a certain pushy trumpeter in the band named Levee angling for his own version to be recorded. A simmering argument about how this song is to be arranged and performed forms the basis of a confrontation about race, sex and power.

Viola Davis plays Ma Rainey with tremendous hauteur: Cate Blanchett’s Elizabeth I never arrived at Hampton Court with more magnificent display or more queenly prerogative than Davis’s Rainey making her entrance, with her own lovers and court favourites, sweating at the temperature, her painful feet and the incompetence of the studio chiefs. And Chadwick Boseman gives a moving performance as the fiercely talented but insecure Levee, crucified by a childhood experience of racist violence and dreaming of fronting his own band.

This is Boseman’s final appearance on screen, and what a glorious performance to go out on. It is a head-butting confrontation of the galácticos: Davis and Boseman are each the immovable object and irresistible force. Amusingly, both are concerned with their feet. Poor Levee has just blown every cent on a fancy pair of shiny shoes and he is always showing them off, hopping and dancing around like a little kid. Ma Rainey’s feet, on the other hand, are in agony. We see her picking her way down the stairs at her hotel in discomfort, yet her rolling, heavy-set gait is part of what imposes her authority on the room. She gets to wear a pair of comfortable indoor slippers in the studio and doesn’t move anywhere she doesn’t want to.

Levee has, quite without Ma’s permission, prepared an ingenious new version of Black Bottom that downplays her slow, bluesy vocals and gives a more demanding, uptempo orchestration for the boys in the band: Toledo (Glynn Turman), Cutler (Colman Domingo), Slow Drag (Michael Potts) and of course Levee himself with his flashy trumpet. This is with the sneaky connivance of the white manager Irvin (Jeremy Shamos) and studio boss Sturdyvant (Jonny Coyne) who sense this is how to make it a lucrative crossover hit.

Ma furiously rejects the new version, sensing – accurately – that this means getting upstaged and that Levee wants to use her prestige as the launching pad for his own stardom. The only male she wants to showcase is her own teenage nephew Sylvester (Dusan Brown) that she capriciously wants to let him introduce the number, despite the fact that he has a stammer. To add to the tension, she has brought along her gorgeous girlfriend Dussie Mae (Taylour Paige), who is dangerously enamoured of Levee.

So who has the power in this contest of wills? In some ways it is Ma Rainey herself – she is the talent, she must be placated, and everything depends on her – yet the band are bleakly unimpressed about her ability to connect with non-black audiences.

Levee has power of his own with new ideas about music, but it is the duplicitous management who control it, and the tragedy and the violence are ignited by the band’s derision at Levee’s sycophantic attitude to these white chiefs. It triggers Levee’s own memories of racist violence and humiliation – and while others in the band get set-piece speeches, too, there is something a bit contrived in these theatrical arias. But they are delivered with such intensity, and the film has a genuine coup in its final scene, showing how Levee’s talent is to be exploited and the way black culture itself is destined to be appropriated.

Boseman’s face is so open, so transparent, so needy – it is an instrument for every painful emotion. It is such a generous performance: the portrayal of a man sacrificed on the altar of his own past.

• Ma Rainey’s Black Bottom is in cinemas from 4 December and on Netflix from 18 December.