This second episode is a captivating exploration of the ocean's wonders and mysteries. It reveals how a significant part of our planet remains unexplored, primarily due to its vast water coverage. The film emphasizes the extraordinary discoveries awaiting every journey below the water's surface, with over a thousand new species identified annually. Home to 80% of all animal life on Earth, the ocean's diverse habitats host a range of surprising behaviors and life-and-death struggles, often hidden beneath a serene exterior.
The shallow tropical seas, appearing as paradises, are actually arenas of intense survival battles. Predatory lionfish, with their patient hunting tactics, and clown frogfish, using a unique fishing rod-like dorsal fin as a lure, demonstrate the ocean's complex food web. The documentary also explores the kelp forests off the North American coast, revealing their role as nurseries for young horn sharks. Amidst these underwater forests lurk giant sea bass, wolf-eels, and various sharks like houndsharks and broadnose sevengills, posing significant threats to the smaller inhabitants. The episode takes viewers to the twilight and midnight zones of the ocean, unveiling alien-like creatures such as the siphonophore, glass squid, and gulper eel, adapted to the extreme conditions of deep waters. The journey concludes with the moving story of the pearl octopus, whose devotion to her eggs in the challenging deep-sea environment is both heartwarming and heartbreaking.
This episode is not only a showcase of the ocean's diverse inhabitants but also a reminder of the urgent need to understand and protect this vast, mysterious, and vital part of our planet.

The deep is perhaps the most hostile environment on earth, at least to us - a world of crushing pressure, brutal cold and utter darkness. We have barely begun to explore it, and yet it is the largest living space on the planet. Scientists already think that there is more life in the deep than anywhere else on earth. This episode takes us on an epic journey into the unknown, a realm that feels almost like science fiction. We discover alien worlds, bizarre creatures and extraordinary new behaviours never seen before. We encounter savage hordes of Humboldt squid hunting lanternfish in the depths and coral gardens flourishing in absolute darkness, with more species of coral to be found in the deep than on shallow tropical reefs. Narrated by David Attenborough.

The second episode of the series immerses the viewer in a fascinating journey through the history of life on our planet, focusing on the evolution and adaptation of life in the seas. It begins billions of years ago, when the Earth was an inhospitable place and life was impossible on the surface due to a hostile environment. The documentary highlights how, beneath the waves, life began to flourish, protected from storms and other elements of nature. It addresses the development of photosynthesis by plankton and how this led to a significant change in the Earth's atmosphere, allowing the emergence of animal life.
This visually stunning narrative chronicles the evolution of various forms of marine life, from the earliest complex life forms to the appearance of the first fish and cephalopods. The documentary shows how marine life has influenced terrestrial life, emphasizing the impact of the 'greening' of planet Earth.

Far from land, where few of us ever venture, is the ocean beyond the boundary of any country. Largely ungoverned, wild, and lawless. Venture into the deep, dark and desolate oceans that are home to an abundance of beautiful - and downright strange - creatures.