Madagascar, the world's fourth-largest island, is a land where lizards scream and monkey-like lemurs sing songs of inexpressible beauty. Where animals and plants that went extinct elsewhere millions of years ago -- tenrecs, fossa, upside-down trees -- thrive in a true Lost World. Where the ancestors of the Malagasy, as the island's eighteen tribes are collectively known, come alive in rollicking ceremonies known as "turning the bones." Here, join Peter Tyson on a diverting odyssey with four scientists out to plumb the natural and cultural mysteries of this extraordinary land.