Wildlife cameraman Gordon Buchanan discovers the nest of the world's smallest parrot, insect expert Dr. George McGavin finds a talking beetle, the scientists identify types of frog, gecko and bat that are completely new to science, and adventurer Steve Backshall has to live and sleep underground as he explores a cave system flooded with white water. The cameras follow the team every sweaty step of the way as they search for the evidence that may help preserve this last great jungle forever.

Second part of the exploration series combining stunning wildlife with high-energy adventure. A team of scientists and filmmakers have made basecamp on a remote extinct volcano at the heart of the tropical island of New Guinea. Their aim is to search the thick jungle for the weird and endangered animals that hide there. Now they are pushing deeper into the rainforest, and enlist the help of a tribe to find and film the extraordinary birds of paradise as they perform their courtship displays.

George McGavin travels east to an erupting volcano and discovers a rare bird that depends on the hot ash for its survival. Sudden explosions bring the trip to a quick halt as giant boulders crash into camp. The series culminates in the lost world of the crater as Steve and wildlife cameraman Gordon Buchanan discover two large mammals that have no fear of people and are brand new species: a giant rat that is as big as a cat, and a cuscus, which is a tree-climbing marsupial.