Steve Backshall goes beneath the surface of Australia's Great Barrier Reef to discover the crucial conditions that allowed a tiny coral building block to create the largest living structure on the planet. He unravels the complex mosaic of reef environments to reveal the key to the microworld's success, but discovers that life on this coast is not always easy. Nutrient-poor water, enormous storms and rising seas should make it impossible for such a vibrant ecosystem to exist here, so what allows the Great Barrier Reef to not only survive but flourish as the largest reef on Earth?
