On the other side of the world under the crystal clear blue waters of the Pacific Ocean lies one of the most enchanting places on the planet. Over ten thousand miles away on the north eastern coast of Australia lies the Great Barrier Reef, one of the natural wonders of our world. It provides shelter to some hidden wildlife sanctuaries that contain some magical marine creatures. Invited on a reef adventure by Emmy Award-winning underwater cinematographer and marine biologist Richard Fitzpatrick, conservationist and naturalist Iolo Williams dives deep beneath the surface of the coral sea to discover what state this natural wonder is in. Together they travel from the extreme swells of the northern part of the reef right down to the cooler pristine corals of the south. They discover how healthy the Great Barrier Reef really is in some of its key locations to see and find out if there are real signs of hope the reef can survive the threat of global warming.

在世界的另一端，在太平洋清澈湛蓝的海水之下，存在着地球上最迷人的地方之一。大堡礁位于一万多英里之外的澳大利亚东北海岸，它是世界自然奇观之一。它为一些隐秘的野生动物保护区提供庇护，其中生活着一些神奇的海洋生物。受艾美奖获奖水下摄影师兼海洋生物学家理查德·菲茨帕特里克的邀请，自然保护论者和博物学家 Iolo Williams 潜入珊瑚海深处，探寻这一自然奇观的现状。他们一起从大堡礁北部的极端海浪一直游到南部较凉爽的原始珊瑚区。他们发现大堡礁在一些关键位置的健康状况，并发现大堡礁是否真的有希望在全球变暖的威胁下生存下来。