Born in the same year as legendary Clash frontman Joe Strummer, filmmaker Julien Temple started working on a film about the band in their earliest days, back in 1976 - but that was before he jumped ship to the Sex Pistols camp. He subsequently became best known for his work with the Pistols on three films - 1977's 'Sex Pistols Number One', 'The Great Rock 'n' Roll Swindle' in 1979 and 2000's retrospective 'The Filth and The Fury'. It was only 20 years later, when Strummer showed up on Temple's doorstep in Somerset, that they rekindled their earlier friendship. Three years after Strummer's death, aged just 50, from an undiagnosed congenital heart defect in December 2001, Temple started work on this documentary.

'The Future Is Unwritten' chronicles the life and times of Joe Strummer - punk rock pin-up and communicator, musician and songwriter, actor and activist, idealist and friend. From his childhood as the son of a career diplomat to squatting in London, playing with The 101ers, personal reinventions, The Clash years, his acting and solo careers, up to his untimely death, 'The Future...' is a comprehensive overview of the complex man that became Joe Strummer.

Alongside a veritable treasure trove of home movies, archival footage, old images and photos, audio recordings and interviews, Temple also uses Strummer's own personal archive, with drawings and doodles animated to mark transitions between scenes. He links talking head footage - Clash members Mick Jones and Topper Headon are interviewed (but not bassist Paul Simonon), alongside Strummer devotees Martin Scorsese, Bono and members of Red Hot Chilli Peppers - by filming fans and friends around a series of campfires in Somerset, London, New York, Los Angeles and Killiney Beach. Alongside the inevitable Clash soundtrack, Temple also uses audio footage from Strummer's popular BBC World Service 'London Calling' show to structure the film.

Although Temple avoids hagiography, showing how Strummer's single-mindedness could both hurt and inspire others, watching how this self-described "mouthy little git" morphed and evolved is a rich and fascinating journey. However, for a documentary that is so thematically accessible, Temple's decision not to identify the interviewees is a mistake. Recognising Martin Scorsese and Johnny Depp (in full-on 'Pirates...' regalia) is not difficult but who, other than the most informed fans, will recognise Palmolive of The Slits? Is that Strummer's wife, Lucinda? Even Bez from the Happy Mondays is not immediately identifiable.

While 'The Future Is Unwritten' is essential watching for fans of Strummer and The Clash, for the uninitiated it is also an involving tale of a man, his music and the inspirations that shaped him.

Caroline Hennessy