What is the reality of life for a crack cocaine user in South London? Daniel Briggs new ethnography is a day to day observation of the people who use the drug, and their struggles to get the drug and also to get off it. He takes Laurie Taylor on an unsettling journey through violence and intimidation.

Also in the programme, eight men in a boat - but how to stop them from pulling in different directions? Anthony King tells Laurie about his research into how a Cambridge crew prepared for and won the Boat Race. He explains the factors which helped and hindered their attempt to establish a rowing rhythm, and discusses what this says about co-ordinating action in society at large. Producer: Charlie Taylor.