Simon follows the magnificent Rocky Mountains south through the USA, from the endless prairies of Montana to the huge prison complex that dominates Cañon City, Colorado. On the way, he encounters Mormon missionaries, North American bison and the policeman of a tiny town getting rich from legal cannabis. It's a world where America's deep divisions - between the country, the cities and between different ethnic groups - are laid bare.
In this third leg of the journey Simon travels down the length of California. In northern California he explores the land of the giant redwoods. Travelling south, Simon arrives on the beautiful west coast where most Californians live. Simon ends the third leg of his journey close to the Mexican border, where the man-made Salton Sea is now drying up, and a once fashionable resort has fallen on bad times.