Such has been the success of the soundtrack album to O Brother, Where Art Thou that the Coen brothers facilitated a reunion of some of the greatest names in bluegrass music at the Ryman Theatre in Nashville. They even had the foresight to hire DA Pennebaker - the godfather of the rockumentary - to film the event. Unfortunately, Pennebaker and co-directors Chris Hegedus and Nick Doob singularly fail to capture the genuine magic of the concert or its significance to aficionados. Casual country-music fans may recognise Emmylou Harris or Alison Krauss but, with no interviews or captions for the artists, they will be left in the dark over the importance of performers such as John Hartford and Ralph Stanley. Compounding the wholly predictable shooting style is a lack of backstage bustle, which is doubly disappointing considering the bonhomie of the rehearsal scenes.