In the finale, the role that fresh water plays in the health of the planet is explored. Included: a kayak journey from the Colorado River to the sea; Kenya's singing wells; and the connection between AIDS and a small fish in Lake Malawi.
An uncharted region of the Amazon is explored. Also: Great Bear Rainforest; farmers in Portugal's cork forests; elephant battles on the edge of the forest in Sumatra; and ancient remains in the Amazon.
An examination of Earth's wildest places and fascinating species, and whether they can continue to coexist with people. First up: large animals, including chimpanzees in Tanzania; tigers in Bangladesh; and giant pandas in China's highlands.