As a rule of thumb, the bigger the star the more outlandish the dressing room request.
It has been reported that Kanye West stipulates Versace towels being on hand at all times, and his missus insists the carpet is ironed. Apparently, Madonna wants a brand new loo seat wherever and whenever she goes, and Van Halen's 53-page "rider" is said to list pickled herring, KY Jelly and M&Ms with all the brown ones removed (to check the venue is paying attention to the tiny details). Other alleged diva-ish demands that have found their way into the press are Mariah Carey's desire for an ever-present attendant to whom she can pass her used chewing gum, and Marilyn Manson asking for a bald-headed, toothless hooker.
Given all that, you'd think a modest requirement of one measly bottle of Coca-Cola wouldn't be too much to ask: a cheap, cold drink to whet the whistle in a sweltering recording studio. Surely that's a basic fridge-filler made available to any rookie performer starting out, let alone one of the biggest singing stars in America.
Not back in the 1920s it wasn't. At least, not if you were black.
That's how the Pulitzer Prize-winning playwright August Wilson (1945 - 2005) tells it in Ma Rainey's Black Bottom, one of his celebrated "Pittsburgh Cycle" of plays, which chronicle the 20th-Century African American experience.
Written in 1982 and first performed two years later to glowing reviews, Ma Rainey's Black Bottom explores talent, ambition, religion, family, race and the historic exploitation of black recording artists by white producers.
It is a black producer, Denzel Washington, who is behind its highly anticipated screen adaptation, soon to be released on Netflix.
The venerated actor has been entrusted by August Wilson's estate to make films of all 10 plays in the cycle, a long-term project that got off to a very good start with Fences in 2016, in which Viola Davis co-starred and deservedly won the Best Supporting Actress Oscar for her performance as an undermined matriarch.
She could well get the twin-set with a leading actress Oscar for her portrayal of the imperious, glorious Gertrude Malissa Nix Pridgett, known to all as Ma Rainey, the "Mother of the Blues".
Davis brings a swaggering, menacing belligerence to a regal character with the soul of an artist, the heart of a lover, and the emotional armour of a tank.
Ma Rainey is not standing for any nonsense from either the cantankerous studio owner Mel Sturdyvant (Jonny Coyne), or her weaselly manger, Irvin (Jeremy Ramos), who has booked the legendary singer to record an album of her songs.
She is not just the smartest person in the room, she is also the most precious commodity, bestowing upon her a status not accorded to most black men and women in 1927 Chicago. Hers is a position of power where she gets to call the shots, but only for as long as she holds all the cards:
"They don't care nothing about me. All they want is my voice. Well, I done learned that, and they gonna treat me like I want to be treated no matter how much it hurt them…. As soon as they get my voice down on them recording machines, then it's just like if I'd be some whore and they roll all over and put their pants on."
The stifling heat in the studio is getting to everybody.
Ma can't sing until she's got her Coca-Cola, her stammering young nephew Sylvester (Dusan Brown) can't get his words out when asked to perform, and her band can't get along with its ebullient trumpeter, Levee (Chadwick Boseman).
This was Chadwick Boseman's last movie before his death in August, a desperately sad fact made even more poignant by the sheer effervescence of his performance as the ambitious, mouthy, naïve, and gifted horn player, who prefers easy ladies to hard work.
The rest of the band are old-timers who know the score.
They turn up on time, play what they are asked to play, and happily shoot the breeze in between. Their professional expectations don't go beyond being paid to play.
Levee was not cut from the same cloth.
He considers himself an artist, a musician from a younger, hipper generation, who knows what the future looks like, and it ain't Ma Rainey's Black Bottom. He wants it all: the flashy shoes, the beautiful women, his own band, and the glare of the spotlight. The problem is he lacks discipline and has a temper as hot as the weather outside.
As tensions rise along with the room temperature, director George C. Wolfe manages the building atmospheric pressure with a controlled assurance, creating a tinderbox of explosive egos and fracturing relationships.
Davis and Boseman are the stars of the show - their characters wouldn't have it any other way - but the overall feel of the movie is of an ensemble piece, with band members Cutler (Colman Domingo), Toledo (Glynn Turman), and bassist Slow Drag (Michael Potts) adding texture and nuance as the ominous cracks widen.
The film is largely faithful to the play, with Wilson's words and extraordinary ear for dialogue treated with the respect it deserves. There are moments downstairs in the band-room (Levee trying to open a locked door) and upstairs in the studio (Ma cosying up to her girlfriend), when it feels like you're watching a filmed play rather than a film of a play. But those occasions are few and far between, and the sense of detachment they provoke is swiftly overcome with a knowing look from Ma or a flash of Levee's smile.
It was a powerful work in 1984 when performed on stage and it remains a powerful work in 2020 on film.
It stays with you. Or, put another way: Ma Rainey's Black Bottom, once seen, never forgotten.
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