On July 2, 1927, the powerful and determined blues singer, Ma Rainey, finds herself at the center of a tumultuous recording session orchestrated by white producers. Her manager, Irvin, has scheduled this pivotal session at Paramount recording studios in Chicago. The seasoned members of the Georgia Jazz Band—Toledo, Cutler, and Slow Drag—arrive punctually, but Ma’s late arrival ignites tensions as her producer, Mel Sturdyvant, grows increasingly exasperated.
Joining the ensemble is the overambitious trumpeter, Levee Green, who is eager to showcase his original compositions and secure a record deal for himself. Unfortunately, his aspirations create friction among his bandmates, who disapprove of his ambition. When Ma finally arrives, she is accompanied by her girlfriend, Dussie Mae, and her nephew, Sylvester. Almost immediately, she clashes with Sturdyvant and Irvin, insisting on her demands, including the provision of Coca-Cola, which had not been supplied. Unhappy, she refuses to start recording until Slow Drag and Sylvester fetch her drink.
Ma’s insistence that Sylvester, who stutters, deliver the opening words of their album leads to further frustration among the musicians. The group struggles through recording "Ma Rainey's Black Bottom" with multiple takes, each time growing more irritable. In an intimate moment, Ma confides in Cutler that her white producers only appreciate her talent, viewing her otherwise as "just a dog in the alley."
Amidst the chaos, Levee engages in a romantic encounter with Dussie Mae, only to be interrupted by Slow Drag. After many frustrating attempts, the band finally completes a track, only to face disappointment as equipment failures render their efforts unrecorded. In the heat of the moment, the band blames Levee, suspecting him of carelessness due to his distraction with Dussie. This leads to an intense discussion wherein Cutler recounts a painful tale of racial humiliation.
Levee dismisses the story, expressing a deep disillusionment with faith, claiming that if God existed, he would show concern for Black lives. This confrontation escalates when Cutler and Levee engage in a physical altercation, with Levee momentarily wielding a knife in defense.
Though the recording session eventually concludes, the atmosphere continues to sour as Ma decides to fire Levee, fearing that his ambition threatens the group’s unity. In a disheartening turn of events, Levee later seeks validation for his music from Sturdyvant, only to find that his groundbreaking work will not be supported, leading him to a tragic mental breakdown. When a heated altercation with Toledo occurs over an accident involving Levee’s shoes, it culminates in a horrific act of violence as Levee fatally stabs Toledo.
As Cutler and Slow Drag flee the scene in terror, a remorseful Levee is left with Toledo’s lifeless body. In the aftermath, Sturdyvant capitalizes on Levee’s songs, but chooses to record them with all-white musicians, leaving behind the essence of the band that once was.
