Like any documentary about a rock band it helps to be a fan but this is a highly interesting one and it's gratifying that this one focuses almost solely on their music development and not on any off stage shenanigans. This film charts the four members early interest in music and their involvement in various musical experiences before finding each other and becoming the unique sounding heavy rock band that broke America before finding an audience in the UK. The interviews are with the three surviving members with some archive interview audio of John Bonham, the drummer who died in 1980. It's a really enjoyable and nostalgic retrospective of the band finding their sound and going all out to sell it. Led by Jimmy Page, the talented guitarist who had learnt his chops as a session musician playing on endless very famous songs including Goldfinger by Shirley Bassey. The colossal riffs of tracks like Whole Lotta Love are given a full airing here and you can't help stomp your foot along with it and you'll then be digging out those old records to listen to with a renewed ear. The film shows that these four guys were hard working musicians which paid off with a new rock sound and success. Early gigs where the audience are too old and have their fingers in their ears will make you chuckle. The film charts their years up to their huge hit second album which implies there might be a follow up of their later period. If that does come and sticks to the same focus on the brilliance of the music then I look forward to it. Until then this is the best rock documentary for quite awhile.