Who made the film (and exactly why) is obscure: a transport employee would seem the most likely bet. Whoever it was has left us with some captivating images of the tube as our grandparents knew it. London Underground users know only too well that their city has since paid the price for having once led the world in underground transport. Unsurprisingly, the infrastructure in this film will look familiar to modern Londoners - it's the passengers who have changed: their dress, their body language, their racial mix, their sheer numbers. This artless series of unedited shots of people moving from A to B has taken on a strange, involuntary poetry over the decades. Is this how CCTV will look to our grandchildren?