As you might expect, there's a strong British contingent at the London Film Festival. The line is being led by such films as the Keira Knightley, Carey Mulligan and Andrew Garfield menage-a-trois sci-fi thingy 'Never Let Me Go' (ably reviewed by Shaun Munro just a few days ago) and 'The King's Speech', which one of the team will no doubt catch later in the week; but beneath the big names of such headline grabbing features are a whole host of distinctive departures from the norm. One of the best among them is docudrama 'The Arbor'. Centred on the life, work and family of writer Andrea Dunbar, the film draws on the experiences of her children, the talents of actors, the wealth of archive footage available and a huge amount of creative input from director Clio Barnard to portray this unique life in a unique way. Though you may not recognise the name straight away, most of you will be familiar with Andrea Dunbar for the film 'Rita, Sue and Bob Too', a story of a messy love affair between two school girls and a married man set in West Yorkshire in the 1980s that she adapted from her own play. The film became a cult hit for its playful-yet-gritty, witty-yet-real portrait of life in Britain at the time, and much of the praiseworthy elements of the film can be attributed to the talents of Dunbar, who relentlessly wrote about what she knew, with a powerful, personal touch that is sadly lacking in a much big screen drama today. In capturing the tragically short life of Dunbar, Clio Barnard adopts a brilliantly unorthodox structure for her documentary. The focus is on interviews with Lorraine and Lisa, two of Andrea's daughters, but only the audio of the interviews was ever recorded. This is a masterstroke for two reasons, firstly because it allowed Barnard to interview the people closest to Andrea Dunbar about some incredibly personal issues (and they are incredibly personal - but more on that later) without the intrusive presence of a large camera crew, and secondly because it left a whole visual sphere free to be filled with whatever best fits the story of these exceptional lives. 'But what could better fit these stories than the faces of its participants?', you may legitimately ask. Well, herein lies the innovation of this film. For you see, Barnard has drafted in actors to lip-sync with the audio, matching what they feel is the emotion and tone of the scene. What's more, they are placed in front of brilliantly evocative scenery that ranges from an almost literal interpretation of the sometimes-harrowing tales told by Lorraine especially to staged versions of the worlds and ideas that surrounded them. Not only is this a great way to free the real-life participants of the documentary, but it is a brilliant reminder of the artifice of any documentary about real lives. And there's even more, occasionally, just occasionally, the powerful emotional material of the family of Andrea Dunbar combined with the masterfully chosen mise-en-scene and the incisive commentary on Dunbar's body of work to provide a moment of clarity that spans several levels. Something that so many documentaries try and fail to achieve. As well as innovations like this (there are more, not least the performance of her play 'The Arbor' on the council estate 'The Arbor' by an actress from the area) that take the subject matter to a level way beyond that of a standard documentary, there is the simple but crucial fact that the Dunbar family are a group of people whose lives have been both blessed and cursed by the genius of Andrea. Lisa speaks carefully of the mother she loved, defending her against any who would speak ill of her troubled life, while Lorraine talks with a cold reserve about how her life spiralled out of control and into prostitution, drugs, and worse. The sum total of this exceptional parts is something that is incredibly difficult to explain without doing it an injustice with oversimplification, but suffice to say that this film, which may seem like a niche-interest documentary at first glance, is rich in structural and stylistic innovation of great importance to the genre, and to top it off the subject matter with which it deals is as intriguing, emotional and dramatic as any you could wish to encounter.