If you like Johnny Cash, you'll like this music- and information-filled movie. And how can anybody not like Johnny Cash? As it's pointed out here, Cash was far humbler than he needed to be. Watching this, I thought about how Cash was a totally no-bullshit guy, a quality you don't see much in the glitzy world of performance today.We learn in this movie the source of the profound sadness that infuses all of Cash's work. But his hardscrabble beginnings and early loss and trauma seemed to have kept Cash honest. The movie beautifully brings out Cash's empathy for the poor and downtrodden. And you feel he means every word.Cash speaks movingly about his past. Living in rural Arkansas, his mother supported his early interest in music, saying, "Well, son, someday you're going to be on that radio set." Interestingly, no family members speak out here -- though, from what I read on Wikipedia, all of Cash's children became singers or songwriters. Still, there are plenty of other talking heads to be heard -- people like Marty Stuart, Chris Kristofferson, and Judy Collins are articulate about a man they learned from and loved. Merle Haggard speaks of how Cash insightfully convinced him not to keep his prison record a secret. Haggard is moving in his description of how life on the road could have led such an artist like Cash to do drugs.There are clips of Cash and his beloved June Carter, but I would have liked to know more about their life together. We see a little of them singing together but learn almost nothing about the drug-related trials and tribulations depicted in the Cash pio-bic "I Walk the Line." Another small problem is that identifiers on many of the speakers are spare or non-existent. For example, it is Jerry Lee Lewis, I believe, who comments on an early sound session with both Cash and Elvis, but who is never identified. So people who are not expert in this realm are left guessing.The music is the best part of this film. Watch Cash perform "A Boy Named Sue" for an inmate audience. There is nothing better!