It will be shown with other short films at the BFI (Tuesday, 7 February 2012, NFT 1, at BFI Southbank, seems to be starting at 18:20) as part of the celebrations around Dickens's 200th birthday...which is, in fact, today.
Details on the Birthday event are here.
A brief description:
The title is taken from Dickens’ essay Night Walks, and his description of London has having “expiring fits and starts of restlessness”. The film takes its own night ‘walk’ and traces the path of the lost Fleet River, through the night time streets of Saffron Hill – once the site of a notorious rookery – and where Dickens located Fagin’s den in Oliver Twist.
I haven't seen it yet, but the stills that are available are, I must say, very intriguing.
And since part of the research was related to Heather's excellent book Artful Dodgers: Youth and Crime in Early Nineteenth-Century London, I'm sure the style is matched with substance.