It is overly long, with a maddening sense of pretension, but at the same time Brett Morgen’s David Bowie documentary Moonage Daydream boasts a pitch-perfect technique in eulogising the iconic pop star’s life and art. Granted unprecedented access to footage and photography by Bowie’s estate, the film works less like documentary and more like a moving collage. It works like memory, ostensibly tracking Bowie’s career from early days to death, but jumping back and forth at the same time. The end result allows for lining up common themes from different decades, and even occasional moments of contradiction – even hypocrisy.

David Bowie died in 2016, just two days after releasing his final album Blackstar. It was a typical album for Bowie really, since he was aware of his terminal illness while recording it. Named after the type of cancer from which he was dying, it was for all intents and purposes a funeral refashioned into an art event; a musical curtain call to his audience. Since his death there has been a veritable landslide of archival releases: collected editions, live recordings, and even entire abandoned albums, all planned by Bowie before his death and given his personal approval. Morgen’s documentary fits seamlessly into this ongoing posthumous wave. It does not merely capture a sense of what Bowie was like, it does so in a style which one imagines would delight him personally as well.

For Bowie fans there is a wealth of behind-the-scenes and live concert footage that is sure to be enjoyed. The film’s soundtrack has been produced by long-time Bowie collaborator Tony Visconti, and blends a wide array of sources. It forms a wonderful soundscape, one peppered with Bowie’s own voice. Morgen has directed and edited a superb montage, combining not just Bowie’s music but his film and theatre performances, and his paintings too. Scenes from his personal life are in shorter supply. This is very much a film about David Bowie as a constructed identity, and not so much the real man at home; it is a better film for it.

Of course the dreamlike nature of the film, which runs in a stream-of-consciousness fashion, means that not every aspect of Bowie’s art gets equal shrift. Fans of his short-lifted heavy rock band Tin Machine will be disappointed, as will those interested in his post-1995 forays into industrial music and drum and bass; the latter is incorporated ably into the montages, but is never really addressed despite being one of Bowie’s most interesting periods.

Goodness knows what the uninitiated will make of it: there is a assumption, perhaps understandable, that anyone watching will already be will familiar with the man and his music. It is a densely packed work, designed to overwhelm. It immerses the viewer in a non-stop cacophony sound and vision. It is great for the fans, but perhaps a little too much for anyone looking to find out why Bowie was so popular. This leads to Morgen’s sole significant failure: the film is simply too long. At 137 minutes it does begin to drag in its final hour. There is a sense of things becoming rushed, which perversely makes it become less interesting. It does not seem to quite know where to end, which leads to a prolonged and weirdly repetitive epilogue. Finally there is an odd reliance on Bowie’s music video to his 1995 single “The Heart’s Filthy Lesson”, images from which are constantly revisited with little justification.

I praise with faint damnation. Moonage Daydream is an excellent celebration of one of the world’s greatest musical figures. While inperfect, it is still an inspiring tribute and a welcome slice of pure cinema.