Whatever your personal opinion of Joe Strummer (and in my experience, opinion see-saws between passionate approbation and scornful dissent), it's hard to argue that one of punks loudest voices (both literally and allegorically) isn't worthy of a biopic.

As director of 'The Filth and the Fury', Julien Temple is already in possession of the requisite punk rock pedigree to attempt such a venture and in a way, it's fitting that he has now served as a documentarian to two of the greatest bands of the twentieth century.

Although 'The Future Is Unwritten' runs over two hours, it's not as exhaustive a documentary as you'd think. The vast majority of voiceover and archive film footage from Clash-era Strummer will be immediately familiar to viewers of Don Letts's magnificent Clash documentary 'Westway to the World' - and indeed many key Clash collaborators (obvious examples include photographer Penny Smith, punk journalist Caroline Coon, Clash impresario Cosmo Vinyl and most incredibly Clash bassist Paul Simonon to name but a few) don't feature as interviewees at all. But then this is film about Strummer the man - the myth - rather than The 101ers, The Clash or the Mescaleros.

Distilling the essence of a complex personality into a feature film is a tricky proposition - but for the most part, it's an expertly executed exercise that's never tedious, never condescendingly extrapolative and never wholly satisfactory - more on that later.

Beginning with Strummer's Turkish birth as public schoolboy John Mellor and his subsequent rebirths as the rockabilling hippy Woody, the counter-culture rebel Joe Strummer and finally the World Service DJ / campfire-loving world music enthusiast father, it's a fascinating portrait of an intelligent, charismatic and intense character.

'The Future Is Unwritten' is predominantly a sympathetic and admiring biopic to be sure, but to Temple's credit, it does incorporate at least a couple of detractive voices. Ex-Roxy DJ and 'Westway to the World' director Don Letts criticises Strummer's cowardice and eagerness to avoid conflict at any cost (a bizarre characteristic given the bellicose and rebellious tenets of punk), while an obviously (and heartbreakingly) still traumatised Topper Headon reveals that his supposed friend routinely stole the affections of his (and his cohorts) girlfriends whilst at their most vulnerable - and that he had to endure his best composition ('Rock The Casbah') rocket to the top of the charts after Strummer had kicked him out of the band.

In the midst of this discord, one wonders why John Lydon, (Strummer's most vitriolic and at punks zenith, most outspoken antagonist) is absent from the film - particularly as all he's interested in these day is filthy lucre. Perhaps the most painful dissention is provided by Strummer's ex-wife - who reveals his relative weaknesses as both father and companion, though whom assuages her criticism by highlighting that Strummer's tortured soul was the root cause of his wayward behaviour.

And it's this character trait that forms the basis of the most revealing segment of 'The Future Is Unwritten'. The story of punk and The Clash is both well documented and widely known, (and frankly done far better in 'Westway to The World') whereas Strummer's walk in the wilderness before he rebounded - both reenergised and reignited with his Mescaleros - is relatively hazy.

Although his protestations that Clash manager Bernie Rhodes tricked him into sacking Mick Jones rings as weakly as an octogenarian in a bell tower, there is no denying that Strummer manipulated others as much as he was manipulated by others.

Strummer's astute and strategic management of the media and general public through the employment of a who-knows-how-well constructed public demeanour (which gave rise to unashamedly derisive commentaries by his contemporaries - and they're hardly surprising upon viewing Strummer's poor approximations of John Lydon's sneering foul-mouthed rantings) is only briefly pondered and instead, most of the second half of the film focuses on Strummer not doing very much of anything at all. It's here that the film pauses for breath and instigates an evaluation and investigation of Strummer's personal life and aspirations rather than merely documenting the fruits of his labour and showing footage of him shouting "Fuck off" to the camera.

Strummer 'the man' is revealed as a character for whom fame was an obsession while success and accolade were things to be feared. Strummer was a man who craved adulation but recoiled from martyrdom and monetary renumeration. At base level, he always wanted to give and never wanted to take - a preponderance that weighed heavy on his mind and led directly to the dissolution of The Clash.

Remarkably, Strummer's legendary 'Walker' soundtrack, his gigs with The Pogues and his little known solo venture 'Earthquake Weather' are all given relatively short thrift by Temple - who instead moves onto Strummer's eventual return to the limelight with the Mescaleros and pissing about at Glastonbury with Keith Allen.

And after all, while it may be Strummer's life, it's Temple's film. His decision to employ vintage footage of the film adaptations of Orwell's 'Animal Farm' and '1984', in an effort to visually corroborate Strummer's socio-political philosophy falls rather flat too.

Although Strummer himself has always maintained that joining The Clash entailed disassociating himself from every facet of his life previous to that moment, (a move he referred to as somewhat Stalinist) - and that The Clash rallied against what they perceived to be fascist governmental interference into the lives of the working classes - Temple's creative decision feels too contrived and exploitative a device.

Far more affecting are the scenes cut from Lindsay Anderson's 'If', used to illustrate Strummer's childhood, and which are made all the more poignant when the film briefly pauses to mediate on his brother's suicide. Animated sequences (created from Strummer's own cartoons) also give a fascinating (if limited) insight into the mind of a man who seemingly had far too many ideas bouncing around to deal with his life and his art effectively.

Yes it's crammed with celebrity accolades, (John Cusack, Matt Dillon, Martin Scorsese et al) but nevertheless 'The Future Is Unwritten' is an engaging and entertaining film (Mick Jones's pontification on the dangers of owning an Oyster card is a belter) that generates as many questions as it endeavours to answer. And in truth, there can be a no more fitting tribute to such a multifaceted character as Joe Strummer.

To wholly understand the man behind the myth would be to dramatically miss the point of his existence, his actions, and his legacy. If Temple's film proves anything beyond a doubt, it's that Strummer's character was that of a true wanderer; a journeyman. In life he was unwaveringly eager to embrace new philosophies, (both spiritual and political) as well as new musical genres - all in the pursuit of a fulfilled self expression and a personal contentment. Thankfully he never succeeded. As Strummer himself would surely acknowledge: It's all about the journey.

If you want a definitive The Clash movie, watch 'Westway to the World'. If you want a definitive Joe Strummer movie, this may well be it. It's not perfect - but then neither was Strummer - and neither are any of us.

One thing though: Strummer had a thing about communal campfires as a venue to talk, philosophise and ponder. I've no problem with this whatsoever, and nor does Temple who elects to exploit this predilection as settings for his interviews. To be fair, most of these are fine with one exception...

Not only does Bono fail to acknowledge that he wouldn't have a career if The Clash hadn't split, he also insists on wearing his fucking SUNGLASSES throughout - even though he's being interviewed next to a campfire...on a beach...in the dark...

Bono is consistent - consistently a fucking idiot in my opinion. Thank God Joe Strummer wasn't.