The film 'London Orbital' is not 'the film of the book' - the book being 'London Orbital' (2000) by Iain Sinclair - rather it is a companion piece to it by Sinclair and his occasional collaborator the director Chris Petit. It is, as would be expected of anything involving Sinclair or Petit, a fascinating but challenging work, a kind of film essay or meditation on the M25 and what goes on on it and around it. Some of the footage is 'straight' documentary, but some of it is hallucinagenic and dreamlike, and there is occasional surveillance and home movie footage blended in. Both directors provide voiceovers and the music is primarily electronic. There are also brief appearances by significant others, most notably the late J.G.Ballard. Petit has been in road movie territory before with his seminal 1979 black and white feature 'Radio On, and journeys are key features of several of Sinclair's books, eg. 'Dining On Stones' (2004) and 'Edge of the Orison' (2005). 'London Orbital' is thought-provoking, atmospheric and totally engrossing, but not - as the other review on this page suggests - to everyone's taste.