On New Guinea, two teams are formed, one of which goes into the Mount Bosavi caldera. The extinct volcano is filmed from the air as the helicopter takes an advance team onto its rim, where they have arranged to meet local Kosua people who will be their guides. They climb down into the volcano crater and prepare a base-camp for the rest of the team. Buchanan films a tree kangaroo, and Helgen helps to identify a wallaby, a painted ringtail possum, a new cuscus subspecies (similar to the silky cuscus), and a large new rat species provisionally named the Bosavi woolly rat.