While elephants and tigers patrol the lush forests of South East Asia, on the Australian side of the Wallace Line, kangaroos and giant lizards roam across vast plains. Safe from large predators, marsupials and strange monotremes have adapted to survive in Australia's harsh landscape. This is the story of how Nature's Great Divide has protected Australia's wild world, allowing life to evolve in parallel, and creating a separate and unique wild realm.

Safe behind the Wallace Line, life in Australia charted its own evolutionary course, in habitats defined by natural borders. This is the story of the wild kingdoms protected by Nature's Great Divide.