Edgar Froese, band leader of Tangerine Dream and pioneer of electronic music, is on a lifelong mission to find the ultimate sound. His constant quest takes him and his fellow band members to worldwide success, all the way to the Hollywood studios in Los Angeles. At his death in January 2015, Edgar Froese leaves a legacy of 48 years of music history. The film shows previously unreleased footage shot by the band leader himself: For the first time, we see the band backstage, on tour in Europe and the US, at photoshoots with Jim Rakete or on holiday at the seaside. Records and interviews with his wife Bianca Froese-Acquaye, with band members, close associates and fellow artists map the unique history of Tangerine Dream: a tribute to the musician Edgar Froese and the era of electronic music.