In each episode of the two series, Middleton visited an extreme area of the world to find out how people have adapted to life there.
In this series, Middleton visited the coldest, hottest, driest and wettest permanent settlements in the world.
Arica in Chile, where there had been fourteen consecutive years without rain.
Mawsynram in India, where average annual rainfall is 14 meters, falling within a four-month period in the monsoon season.
In his second series, Middleton visited places without permanent towns, locations where "survival requires a lifestyle completely in tune with Nature's rhythms."