the documentary begin with set the perspective to several light year . the voyager be travel our milky way with the sound of our earthly life and a a space monument for ( possible . ) extraterrestrial . the documentary contains footage of willy dixen and robert johnson and skip james and j. b. lenoir . the footage of j. b. have never be publish before . the narrative be from blind willie dixon . however and it do by an actor . the film show the work of all these early blue men follow by cover and interpretation by musician and such a nick cave and the bad seed among others . the death of j. b. lenoir ( john mayall song ) be a striking event in the story . lenoir get political engaged and be consider to be of the league of martin luther king and peer . his political interest can be find in the theme of his lyric . blue be find to be the native music of america . blue be the root and the rest be the fruit . the title soul of a man be after a willie dixon song .