Robert Altman was one of the most important, challenging and visionary American directors off the last 40 years. Despite myriad setbacks and periods in the wilderness, he made some of the most influential films in modern American cinema. Despite never winning an Oscar for any of his movies, he was recognised by the Academy with an Honorary Award just before his death. Not only did he challenge the system with his naturalistic style, but he also made pioneering breakthroughs in filmmaking itself.

Ron Mann’s documentary starts with Altman’s early life, from serving in the Air Force to his first forays into TV. Using voiceovers from his family, archive interviews, home videos, clips and on-set footage, he plots Altman’s journey from a young chancer to one of the most globally respected filmmakers. Mann builds-up a complete picture of a man who’s passionate about what he is doing, unwilling to compromise and has a deep affection for his family; both biological and cast.

In total, Robert Altman was nominated as Best Director on five occasions, for M.A.S.H., Nashville, Short Cuts, The Player and Gosford Park. It’s a travesty that he never won an Oscar for any of his films. He dragged the Hollyood establishment forward both in terms of technical advances and thematic considerations. Sadly, his anti-war stance and derision for the establishment led him to being appreciated much more in Europe than his own country. Ron Mann’s film epitomises why Altmanesqe will forever be a byword for innovation, courage and vision for directors for decades to come.

Altman is out in cinemas on Friday.