Overview:Jeremy Clarkson, Richard Hammond and James May are dropped deep in the Bolivian rainforest armed only with three 4x4s which they bought from the local small ads for a maximum of £3,500 each. They attempt to drive from the heart of Bolivia to the coast of Chile, encountering drug lords and the debilitating effects of high altitude. Without a doubt one of the toughest challenges the `Top Gear' team has ever faced.