"O Brother, Where Art Thou?" is a Coen brothers' movie claimed to be based on the ancient Greek masterpiece "Odyssey" by Homer, yet transplanted thousands of years later to Mississippi, USA, and accompanied by abundant early American folk music. It is dramatic and humorous. Actors and musicians are the very best of their kinds. It received the highest critical acclamations and prestigious awards. For years there have been countless scholarly studies, general comments and even tabloid news about this film. It even evoked a rejuvenation of interest in American folk music. This article is a study of the characteristics of this film with an emphasis on its musical aspects.