Tonight's episode uncovers life in Olusosun rubbish dump. Here, around a thousand people live on top of the rubbish in houses built from scrap. It looks like the end of the world, but the film reveals that there is order – and honour – among this seemingly chaotic environment. There are shops, bars, restaurants, cinemas, even a mosque, and the scavengers have set up their own kind of government, with a democratically elected chairman at the head.

Lagos's version of Venice is a slum, built on water, called Makoko. This three-part observational series continues to explore one of the most extreme urban environments on the planet, by taking a trip into the lives of those who choose to live and work on the waters of Lagos Lagoon. Chubbey is a fisherman who lives in a house built on stilts. With 18 children and five grandchildren to support, he has become an expert at making money from the most unlikely of places. Whether he is building a fish pond in the same water he uses as a lavatory, or renting out a spare room which he has not even built yet, he has always got some scheme or another on the go. But when his teenage son starts to hang out with a local gang, he is left with a dilemma familiar to parents all over the world.

For over six years, Esther has been living with her husband Segun in a house they built themselves from cardboard, scrap wood and tarpaulin on the beach in central Lagos. Every time the government send their task force to bulldoze their village, she and the thousand or so other inhabitants soon pick up the pieces and build another one. Her best friend, Blessing, is about to give birth here in a few weeks and Esther is worried for her safety. But when she discovers text messages from another woman on her husband's phone, she suddenly has problems of her own to deal with. Meanwhile, politicians in Lagos are planning sweeping changes to improve the infrastructure and attractiveness of Lagos. Part of their plan to turn it into a 'megacity' involves demolishing the slums, which house so many of its inhabitants. The film follows Sagede, a member of the newly established Lagos State Environmental and Special Offences Enforcement Unit, which targets illegal dwellings all over the city, clearing away everything in their path.