The well-known actress and world champion in freediving, Marina Kazankova, presents the most beautiful and wonderful reef in the world: the Great Barrier Reef in Australia. Threatened by the ongoing global warming and over acidification of the ocean, it is fighting for the preservation of this unique UNESCO World Heritage Site. She takes us on an extraordinary journey from the Hardy Reef across the Whitsunday Islands to the unique Coral Cays. It is accompanied by a variety of reef-based life forms such as whale sharks, turtles and the rare, up to three meters long giant grouper. Once again we experience the underwater world of the world’s largest reef with its hidden caves, mysterious shipwrecks and fantastic horizontal waterfalls.