Petropolis, Aerial Perspectives On The Alberta Tar Sands

There have been a spate of environmental documentaries in recent years; to an extent they are all competing for a limited supply of public sympathy. They also face frequent challenges from the industries they criticise as they struggle to present a perspective that cannot be accused of bias. Petropolis takes the unusual step of including almost no narration, with just a few subtitles at they start explaining what it is we're observing from the air. Together with a subtly crafted soundtrack - ambient electronic music, rustling trees and birdsong - this gives the impression that readers are entirely free to construct their own narratives. In reality, however, the carefully arranged visuals tell a very particular story.

This unusual construction is not the only thing that makes Petropolis stand out from the crowd. In my job I see a lot of beautifully shot films, but the cinematography in this one is simply breathtaking. From the start it will grip you with the clarity and natural splendour of its dramatic aerial views. Of course, it needs to, because for most of its duration this is all you will have to look at, but it's so elegantly constructed that you will feel as if you're actually there. It's easy to imagine the scent of the pine trees, the strange odour of the asphalt marsh, and the clogging fumes of the industrial stations where fuel is extracted and processed, leaving huge areas of land stripped bare.

Travelling around this fantastic landscape in a light aircraft, we see soft curves, gently blowing trees, a rushing river. It's a shock to be confronted with the stark geometry of industrialisation. As they are processed, areas of land are divided into stark, unnatural shapes, mirroring the squat forms of the warehouses, their metal shells stained sulphurous yellow. A town grows up, presumably the miners' residence, prefabricated housing alien in this vast place. Each day, we are told, as much carbon dioxide is released from this process as from all the cars in Canada.

Different as it is, this won't be for everyone. If you don't like slow films, forget it. The early scenes are the strongest, and towards the end the film begins to run out of things to say (even silently), until sudden speech snaps the audience out of their reverie. It's odd to hear a human voice intruding in this stillness, itself reminiscent of the physical human presence. This isn't quite the neutral film it pretends to be, but the argument it does make is compelling, and it's a quite extraordinary piece of work.