An island cut off from mainland Australia for ten thousand years turns out to be a laboratory of oddities, and David Attenborough narrates a tour of what evolved there in isolation. Tasmanian devils snarl and scrap over carrion in ancient eucalyptus forests, white wallabies move through button grass plains found nowhere else, and miniature penguins come ashore at dusk on beaches ringed by dramatic coastline. The film follows eastern quolls hunting by night and finds glowing worms lighting up cave walls and damp forest floors, a bioluminescent display most visitors never see. Tasmania's seasons drive the story: rivers swell, giant trees put on decades of growth, and animals time breeding and feeding to a rhythm shaped by the island's temperate extremes. Cameras get close to burrows, riverbanks, and forest canopy to show behavior rarely filmed elsewhere. The result is a portrait of a small, cold, wet island that behaves like a separate evolutionary experiment from the rest of the continent it broke away from.