Kate Humble investigates how tough life is for an Afar woman; Steve Leonard wants to learn about the relationship between the Afar and their animals, and to help with animal medicine where he can; Dr Mukul Agarwal looks at the health issues faced in this most hostile of environments; earth scientist Dougal Jerram looks at the extraordinary volcanic activity of the region and the part it plays in the bigger geological picture of the Rift Valley; and biologist Richard Wiese searches for extreme life forms in the boiling soil of a massive volcanic fissure.