By Madison Vain
September 10, 2015 at 05:12 PM EDT
Beth Gwinn/Redferns

Johnny Cash had an epic third act. It’s often passed over in remembrances of his 50-year and 100-album career, but CMT’s new documentary, American Rebel: Johnny Cash, which premieres Saturday, Sept. 12 on the network, delves into its fray.

Off his 1969-1971 variety show, Cash began touring again but it was to increasingly smaller audiences. When interviewed for the documentary, John Mellencamp spoke of remembering when Cash lamented to him that he thought his only option left was to become a Branson, Missouri novelty act. Cash fell back into drugs in the early-’80s, was dropped from Columbia Records, the label he helped build, and music, as he says via a taped interview in the film, had lost its magic.

At the same time, legendary producer and co-founder of Def Jam Records, Rick Rubin, was looking to take on a project with a legacy act. He wanted a storied performer who had fallen on hard times. It didn’t take too long before they found each other and American Recordings, which would grow into six albums released over a decade of working together, began to take shape.

Jim Steinfeldt/Michael Ochs Archives/Getty Images

“Rick Rubin and my father had a great friendship and it’s because of it that the work my dad did at the end of his life was created — that he felt creativity and invigorated again, even though he was being consumed by frailty,” John Carter Cash tells EW in a recent interview. “He was having Parkinsons-like symptoms, reoccurring bouts with pneumonia, broken jaw, missing my mother after she passed; he was blind, not many people know that. So there was a steady decline in many ways, but there was a far greater rise in strength. To have Rick relate that personally [in the film] was unique.”

Rubin speaks at length in the film about their partnership. About drawing the Man in Black back out, of building him up. But it comes across as less of an accomplishment for Rubin than it does an experience in which he was equally rewarded, a partnership he valued for personal and professional reasons just as much. And the rest of us, well we got an extra decade of fine Johnny Cash material.

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