World in motion: "Human Flow"

Visit 180 The Strand, a towering office block that has in recent months been appropriated as a temporary exhibition space, before this weekend is out, and you'll be confronted by a work that the dissident Chinese artist Ai Weiwei has entitled Odyssey: one side of an entire room decorated from ceiling to floor in what at first appears to be mass-produced wallpaper. Get in close, however, and you notice that what looked from afar like generic patterns are in fact scenes from the 21st century's refugee crisis. Here are men, women and children fleeing the sites of conflicts, taking to the seas in overcrowded dinghies, occasionally meeting sorry demises, being threatened by border guards and anybody else opposed to the principle of free movement. The key to understanding the work - and, just perhaps, the world - is that you have to go out of your way and really look. Human Flow, the epic new documentary to which Ai has signed his name, is Odyssey as retold in moving images - a big-picture artistic statement that seeks, in its 140 minutes, to bridge East and West, Europe and Africa, and to embrace Syrian, Rohingyan and Kurd alike. It is at once hugely ambitious and massively unwieldy; its triumph may be that it gets as far and covers as much ground as it does before it collapses over the finish line.

One might best approach it as a primer, or - perhaps better, given Ai's fondness for sweeping, vertiginous drone shots - an overview, flashing up facts, newspaper headlines and quotes over footage taken at those points of arrival and departure. Here, we find Ai - persona non grata in his native China, as the excellent 2012 doc Never Sorry reminded us - greeting those tumbling onto and off those dinghies, and those left in limbo in damp tents in railway sidings. (His attempts at making conversation and connections with those he finds there, often involving broken English and smartphone cat photos, are reliably charming.) The Google Earth framing ensures Human Flow remains at all times more specific than last year's free-roaming, impressionistic portrait Fire at Sea, which left its audience to feel out its terrain for themselves. Ai's film, by contrast, is governed by the same sequentiality as the artist's wallwork: he shows us the bombed towns and cities, and the homes rendered uninhabitable, then the displaced masses, then the perilous journeys they undertake - across rocky roads and fast-flowing waters - to reach some form of sanctuary. In doing so, Human Flow expresses a logic that may, in the unlikely event of the film being given away as a cover-mounted DVD with the Daily Express, help chip away at some of the less rational rhetoric that has hardened and solidified around this topic. 

Migration is here framed as a matter of logistics - huge crowds, moving in a particular direction, and leaving our gatekeepers with three options: repel them, rope 'em off, or reintegrate them somewhere else. As one migrant wonders, peering at Ai's camera from the other side of a chainlink fence: "Border closed? Where the people go?" These are the questions (and uncertainties) that hover over every frame here, and you do sometimes wish Ai had alighted upon more in the way of practical solutions - though this may be our leaders' failing, not the film's. (Either way, no 2017 release has cried out louder for post-screening Q&As: the tone and phrasing will vary, but every image will likely prompt a response of "What can I do?") The scope dilutes its charge: as politically charged art, Human Flow proves less effective than Odyssey, which reduced the refugee experience to the stark essentials of survival, and made its repetition seem a vital part of the piece, rather than an editorial oversight. Nevertheless, this is a comprehensive and exhaustive study, and self-evidently the kind of work only an artist whose heart is as all-encompassing as his gaze would embark upon. Human Flow succeeds in reconciling the grand gesture with the tiniest detail; it opens up the space still available on our planet, then gets in close enough to see the humanity in our fellow travellers' eyes. The big question is: where do we all go from here?

Human Flow opens in selected cinemas from tomorrow.