On demand: "The Gift: The Journey of Johnny Cash"

The editor-turned-director Thom Zimny has hitherto been most closely associated with Bruce Springsteen, overseeing the Netflix gig Springsteen on Broadway before collaborating on the rocker's concert-film-cum-album-promo Western Stars. With The Gift, we find Zimny stitching together a feature-length documentary tribute to Johnny Cash at the behest of YouTube's new Originals label. (Two, in fact: the film exists both in a 94-minute form and a 115-minute "Bonus Cut" available to premium subscribers.) There are obvious points of comparison between Zimny's subjects of choice. Both presented themselves as outlaw rockers, fighting with music and lyrics for what is just; both fumbled their way towards an idea of America, and an indigenous, identifiably American music; and as Western Stars (film and album) made clear, both men wrestled with the tension that exists between the loner and family man, navigating between going their own way (personal and artistic freedom) and returning to the homefront and the company of the one or ones they loved (dependency of one form or another). Zimny has become the pre-eminent chronicler of rock's sincere wing, in other words. You could take Bruce or Johnny home to meet your mother; you could only take home Elvis or Jerry Lee if you'd troubled to lock up the town's daughters - and, who knows, maybe even some of those mothers - beforehand.

The "gift" enshrined in the title is the name Cash's mother Carrie gave her son's voice after it broke some time in the early 1940s - that gravelly, authoritative timbre that at times sounded indistinguishable from some imagined voice of God. With no better qualified narrator, Zimny endeavours to give us Cash in his own words, using a series of audiotaped interviews to nudge his biography onwards between extracts from the key recordings, starting with 1955's "Hey Porter" (which may strike some listeners as the singer's "Rock Island Line", were Cash not then heard covering exactly that) and bound for his comeback recordings with the producer Rick Rubin. One advantage of watching the film on YouTube: presumably you can pause and open up a new search window, if one of these tracklets takes your fancy. The great editorial advantage The Gift has over 2005's enduring Cash biopic Walk the Line is that paints a considerably fuller picture of the ups and downs of this life - the hard yards that led to the earlier film's happy ending. We're introduced to Johnny before June, the outlaw Man in Black spending long days and nights on the road building a name and career for himself, propelled by all manner of stimulants; we become aware this is exactly the kind of wearing schedule that might well make a man yearn to settle down. Among the treasure Zimny has loosed from the archives: gorgeous photographs of his subject stripped of all greasepaint and showbiz lustre, looking properly dogtired - here is the fatigue Joaquin Phoenix worked into his performance in the biopic.

We know the second act already - Cash finding somebody to harmonise with, offstage as on - yet The Gift benefits from the return to primary sources: video and photos collated from his time together with June show a visibly sunnier and happier Cash, while electric footage of the singer duetting with The Carter Sisters on "Were You There?" is about all the proof you could want of how effective this pair were professionally. Yet equally, here are Johnny and June after the Hollywood happy ending, their offspring on hand to talk us, with typical candour, through the drug addiction (lingering side effect of life on the road, or something new?), the rows and the unhappy slide into creative complacency. Of course, Cash kept the faith, kept walking that line, which led to Rubin and his eventual rediscovery: here is an American life that very definitely had a triumphant third act, which explains why our filmmakers have been drawn to it so. In many other ways, however, this journey was unusual, atypical, more 20th century than 21st. That "Were You There?" clip is central to The Gift - Zimny places it around the halfway mark - because it underlines the deeply felt spiritual aspect of this life, bound up with Cash's upbringing among the churches and preachermen of the Deep South. Zimny's film posits that Cash understood all along that his voice was God-given, and that at a certain point resolved to use it for good; that whenever he sinned, he pledged anew - with each song - to redeem himself and others. (Springsteen, a secular saint raised amid the business-is-the-new-religion mindset of post-War America, seems to have been liberated from this burden; perhaps it bears down more heavily on men with the initials JC.)

This allows the film to broach Cash's progressive politics (where Walk the Line confined itself to rustbelt-pleasing romance): the causes he championed, the rows with radio stations, the arrests. Possible to sense that, one way or another, Cash was always going to end up in Folsom Prison, a site foregrounded in Zimny's prologue; it's just that he chose to go there, at a moment in his career when he had the power to do so, and when doing so would do the greatest good. Love - the love of a good woman; his lifelong love for this music - pulled him through any remaining tests. As the distance between Cash and the rest of us grows, it becomes ever clearer that he was redeemed in a manner of speaking, which is why this continues to stand as one of pop's most moving stories. It remains a hell of a life to have to try and sum up in 94 minutes, when the basic narrative components would more readily suggest some Biblical epic. (It may well be that the "Bonus Cut" - also available on YouTube - allows Zimny greater room to breathe, and to pull more treats yet from the archive.) I suspect at some point we'll get a long, multipart Cash doc such as Scorsese has given us on Dylan and George Harrison, and Alex Gibney gave us on Sinatra, and that it may stand as definitive: you won't mind hearing the songs again, because these songs were built to last, with good motors and gas in the tank. In the meantime, The Gift will be near-essential to fans, while even a casually interested onlooker like your correspondent couldn't fail to be struck by the extraordinary poise Cash displays in one clip - an aside in concert footage doubtless buried elsewhere on YouTube, but here spruced up in 1080p streaming resolution - while turning down a fan's offer of a mid-gig swig of bourbon: "I don't drink any more. I don't drink any less, I just don't drink any more." It isn't just the voice, Zimny's film understands; it's what you choose to do with it.

The Gift: The Journey of Johnny Cash is now streaming on YouTube.