In 1987, an elderly lady, Hattie Mae, visits Johnathan, the current Attorney General of Hopewell, Georgia, who is seeking re-election through his racist political ideologies. Hattie asks him to solve the murder of her son, Bayou, who was lynched in Hopewell in 1947, by providing his extensive letters to his love, Leanne Harper.

Bayou comes from an extensive family of musicians, with his talents being a singer while his brother Willie Earl plays instruments. Bayou meets Leanne, an educated but outcasted girl, and the two fall in love. They have secret meetings at night, but they are unable to be together publicly due to the disapproval of her family, including her grandfather who sexually abuses her. They become separated after Leanne's mother forces her to move to Boston.

The two encounter each other again in 1947 after Leanne moves back. Bayou helps his mother run a successful juke joint, while Leanne is married to politician John, the brother of Sheriff Jackson, and is forced by her mother to pass as white for financial stability. The two reconnect and rekindle their love in secret. When Leanne's mother catches them together again, she lies to the sheriff, claiming that Bayou had whistled at Leanne. To escape the mob coming to lynch him, Bayou is whisked off with Willie Earl and Willie's manager, Ira, to Chicago where he becomes an unexpected hit at the Capital Royale club.

Despite his success, he is unable to forget Leanne. When he hears she's given birth to a baby, he realizes that she has given birth to his son and he plans a one-night return to Hattie Mae's juke joint to rescue her. Under the guise of returning to help revive his mother's juke joint, Bayou makes his way back to Georgia. Willie Earl, jealous of his brother's success, tips off Sheriff Jackson that Bayou is back in town. Bayou is reunited with Leanne and their baby, but a mob lynches Bayou to the distress of Leanne and Bayou's family.

Johnathan, who is Leanne's son, is stunned after reading the letters and concludes that he is Bayou's son and Hattie Mae's grandson. Johnathan visits his mother and hands over the letters Bayou had intended to send to her, moving her to tears. He then goes outside and is left to reckon with the truth of his birth.