Through musical archives and numerous interviews, "Mr. Brown" recounts the entire life of James Brown from 1933 to 2006, focusing primarily on his years of struggle and glory between 1955 and 1971. This film also recounts the world in which the artist evolved. Numerous witnesses recount their experiences with the artist and the man they knew: saxophonist Pee Wee Ellis, trombonist Fred Wesley, bassist Bootsy Collins, MC Danny Ray, and singer Martha High.