In 1955, a tough, skinny guitar-slinger who called himself J.R. Cash walked into the soon-to-be-famous Sun Studios in Memphis. It was a moment that would have an indelible effect on American culture. With his driving freight-train chords, steel-eyed intensity and a voice as deep and black as night, Cash sang blistering songs of heartache and survival that were gutsy, full of real life and unlike anything...