Film-makers from the BBC's Natural History Unit and scientists from America's Smithsonian Institution venture into Burma's jungles to catalogue its species in the hope of getting protected status for the area. The team sets out to discover whether the mountains in the west are home to a population of Asian elephants that could prove critical to the survival of the species. Gordon Buchanan and Justine Evans search the valleys and ridges, while biologist Ross Piper follows up rumours of a second herd.