Director — and piano player — Clint Eastwood explores his life-long passion for piano blues, using a treasure trove of rare historical footage in addition to interviews and performances by such living legends as Pinetop Perkins and Jay McShann, as well as Dave Brubeck and Marcia Ball.

Barbara Graham is a woman with dubious moral standards, often a guest in seedy bars. She has been sentenced for some petty crimes. Two men she knows murder an older woman. When they get caught they start to think that Barbara has helped the police arresting them. As a revenge they tell the police that Barbara is the murderer.