The Great Barrier Reef abounds with life. But it is under attack from above and below the water. A team of marine biologists and geologists investigates how the reef was born, what makes it thrive, and how it may disappear in our lifetime. Biologists take viewers below the water to discover the foundations of the reef, and the cycle of life that keeps it alive. These scientists investigate the earliest formations of the reef and try to answer the question of how long it can survive. Three bonus features explore other oceanic wonders, from the Challenger Deep to the volcanic islands of Hawaii, and new marine life forms all over the world.