The film opens in 1993 with James Brown (Chadwick Boseman) walking through a darkened hallway as an audience chants his name. He hears the voices of people he knew throughout his life. The film then cuts to 1988 in Augusta, Georgia; James learns that his private bathroom in a strip mall he owns was used without his consent. As he confronts and then forgives the trespasser, he accidentally fires a shotgun, attracting the police.During the 1960s, James and his band decide to travel to Vietnam to show support to the black troops, where they put on a well-received show. In 1939, James is raised in the woods by his parents (Susie and Joe Brown), whose marriage is fraught with financial struggles and physical abuse. James performs in a singing group, The Famous Flames, formed by Bobby Byrd (Nelsan Ellis), whose family sponsored his release from prison, a penalty he paid for stealing a suit.James lives with the Byrd family and becomes lead singer of Bobby's group. In 1964, manager Ben Bart convinces them to let The Rolling Stones close The T.A.M.I. Show instead of The Flames. The Flames upstage the Stones, and, exiting the stage, James tells the Stones, "Welcome to America". In James' childhood, Susie leaves Joe, and Joe threatens her with a gun and keeps James. Joe continues to abuse James until Joe joins the army. James is left living with and working for his Aunt Honey, who runs a brothel. At her home, he attends church and enjoys the choir.At the age of 17, James steals a suit, is arrested, and receives a five-to-thirteen-year prison sentence. In prison, James sees a group of singers performing. His enthusiastic reaction incites a riot wherein both he and one of the singers, Bobby Byrd, are injured. Bobby invites James into the Byrd household. Years later, James joins Bobby's gospel group and they put on a show at a club as The Famous Flames, following a performance by Little Richard. Another flashback from James's childhood shows him and other black boys forced into a battle royal boxing match while a band plays. Inspired by the funky band, James wins the match.In the 1950s, James and Bobby meet an agent from King Records, with whom The Flames record their first single, "Please, Please, Please", on the Federal Records label in 1956. King Records executive Syd Nathan initially mocks the song but appreciates James's vocals. Ben Bart becomes James' manager, calling him the true voice of the group. The records are labeled as "James Brown and His Famous Flames", leading all the members except Bobby to quit. James and Bobby form a new band with Maceo Parker, Pee Wee Ellis, Nafloyd Scott, and Baby Roy.The Famous Flames singing group is also re-formed, replacing the members that quit. The Flames perform at the Apollo Theater to an excited audience. After the show, Bobby tells James that a lady claiming to be his mother is there. As a young child James had seen Susie with a soldier, to whom she claimed she didn't know James. Aunt Honey consoled James, saying that his mother was a fool and James would someday be rich.James has a child, Teddy, with his first wife Velma. He later divorces her and marries Dee-Dee. On one occasion, the couple hosts a Christmas event. Afterwards, James hits Dee-Dee for wearing a revealing outfit. In an attempt to reach out to the black community, James records the song "Say It Loud - I'm Black and I'm Proud" (1968) with a group of children. James convinces the Boston Garden' manager to not cancel a performance following the assassination of Martin Luther King, Jr.. Several people try to get on stage; security guards intercede until James controls the audience.Over time, James manages the band poorly, and they all quit. Ben dies of a heart attack. Bobby muses about a career as a lead singer, leading to a heated argument with Brown, who tells Bobby that, although Bobby's wife Vicki Anderson (who was a featured singer in Brown's Revue) could be a major solo performer, Bobby could not. Angry and upset, Bobby fires back at Brown, and after Brown makes some cruel statements, finally leaves him for good. Backtracking several years, to an incident at the Apollo, Brown's mother Susie appears backstage during a Flames concert and expresses her love for James despite her reluctance to be a mother.After she leaves, Bobby comes back in, sees James having a breakdown, and heeds his request to take care of Susie. In 1973, James learns Teddy has been killed in a car accident. Immediately before the incident at the strip mall, James smokes a joint laced with angel dust. The police chase James and arrest him.In 1993, James meets Bobby for the first time since Teddy's funeral to give him tickets to his show. James walks onto the stage through a darkened hall. He sees visions of people from his life chanting his name. His performance of "Try Me (I Need You)" moves Bobby and his wife Vicki to tears, and the audience cheers.