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.

Explore the breathtaking extremes of our planet in this captivating episode. Journey through the vast Hang Son Doong cave in Vietnam, the largest on Earth. Witness the resilience of life in harsh conditions, marvel at the adaptation strategies of species like the blind cave fish and the enduring Arctic wolf pack. In the Arctic, observe the strategic hunt of wolves preying on musk oxen, a dance as old as the Ice Age. In the French Alps, the struggle for mating among common frogs unfolds, showcasing the urgency and challenges faced by cold-blooded animals. Witness the social dynamics of Barbary macaques in the cedar forests of the Atlas Mountains, where survival hinges on social bonds. The forests of Mexico, home to millions of monarch butterflies that huddle for warmth, illustrates the fragility and beauty of nature.
Discover how fire shapes ecosystems in South Africa's fynbos and Northern Australia, crucial for the survival of species like the golden-shouldered parrot. The documentary poignantly addresses the impact of changing climates and human intervention on wildlife, from the endangered elephants of Amboseli, Kenya, to the secretive snow leopards of the Gobi Desert. This episode offers a profound glimpse into the extraordinary adaptations and challenges faced by wildlife across the globe, reminding us of the delicate balance and beauty of life on Earth.

Continuing your bloodline is life's ultimate mission. In this unpredictable world, animals will do whatever it takes to keep their families safe. When family sticks together, communicating, collaborating and combining as one, everyone has the very best chance of survival. It takes every superpower possible to protect and provide for the family and secure the future for a new generation of amazing animals.

In the quest to pass on their genes, animals use incredible skills to win a mate. And spectacular displays to beat their competition. When the fight for mates gets fierce, it could take super strength and secret powers just to keep rivals at bay. After all, when it comes to sharing your future, only the most super-powered partner will do.

The natural world is full of colours. For us, they are a source of beauty, but for animals they are a tool for survival. David Attenborough reveals the extraordinary ways in which animals use colour: to win a mate, to fight off rivals and to warn enemies. New camera technologies - some developed especially for this series – also allow us to see colours and patterns usually invisible to human eyes.
Ultraviolet cameras reveal bright signals on a butterfly’s wings and facial markings on yellow damselfish that are used as secret communication channels. Some animals can also detect polarized light, and specialist cameras can now show us how fiddler crabs see the world, and how mantis shrimp have strange polarization patterns on their bodies to signal to a mate or rival.

An astonishing close encounter with some of the most exotic creatures inhabiting the hidden depths. In the realm of the giant octopus, the rainbow nudibranch (sea slug), and the Scorpion fish, viewers become a fearless undersea explorers, discovering the strange and unusual partnerships these 'star wars' creatures forge to ensure their survival, and learning how this cooperation allows life in this enchanting world to flourish. Filmmaker Howard Hall guides an astonishing adventure. Johnny Depp and Kate Winslet narrate as Green Sea Turtles gather so Surgeonfish can strip harmful algae from their shells. A Humboldt Squid changes color four times per second like a flashing strobe light. A Mantis Shrimp’s claws have the speed of a bullet in battling a hungry octopus. Brace yourself to be submerged in a wondrous new dimension.