Sir David Attenborough explores the surprisingly vibrant seas that surround the British Isles. The vast watery wilderness around us is over three times the size of our land mass, and yet to many, our oceans remain a mystery. Full of colour and teeming with life, the seas of Britain and Ireland are crucially important to a range of wildlife. This episode goes beneath the waves to uncover the thriving habitats that exist along our 22,000-mile coastline.
In winter, clear evidence of the ocean’s abundance can be seen on a beach in Norfolk. Thousands of grey seals congregate on the shoreline to give birth. Britain and Ireland are home to 40 per cent of the world’s grey seals, and the number being born on our shore rises every year. Once the newly born pups are weaned, the females are ready to breed again, and heavyweight males enter violent, bloody fights to win a stretch of beach, and the females along with it.
Beyond the beach, the vibrant shallows contain several important habitats. Rich beds of seagrass are nurseries for a range of animals, while also acting as very important carbon storage areas. They are also home to one of the strangest fish in our waters, the seahorse. We follow a male and female as they perform a balletic mating dance in the water, delicately entwining their tails. The stakes are high, as these animals mate for life.
In a touching piece to camera, Sir David bids a fledging Manx shearwater chick farewell as it embarks on a 6,000-mile journey across the oceans to South America. There is no better example of how important the British Isles and its abundant seas are to the survival of wildlife worldwide.

In an enthralling documentary, Dan Snow and archaeologist Raksha Dave delve into the catastrophic impact of the Black Death on Britain 700 years ago, a pandemic that extinguished around half of the population, or three million people. The duo embarks on a journey to trace the origins and merciless spread of the plague, starting from its arrival on Britain's South coast in June 1348, through the bustling trade routes that brought the disease to Melcombe Regis, Dorset. Their investigation takes them to various hotspots of the outbreak, including the Old Operating Theatre in London and Wildwood Animal Sanctuary in Kent, where they explore the role of rats in dispersing the bubonic plague. Through dramatic reconstructions and visits to places like Nottingham University's biomedical laboratories, they uncover the rapid spread and deadly impact of the plague, offering a month-by-month account of how it ravaged the country, decimating cities, towns, and villages alike.
The documentary not only showcases the horrific symptoms and desperate attempts at cures through brutal medical practices of the time but also leverages cutting-edge research to explain why the Black Death remains the deadliest pandemic in history. The personal stories of victims, from princes to paupers, are brought to light, revealing the indiscriminate nature of the disease. Dan's visit to Canterbury Cathedral and Raksha's investigation into the recent discovery of mass graves beneath a tranquil London square underline the widespread desperation and devastation. Their journey through the history of the Black Death, culminating in the discovery of its indiscriminate toll and the unveiling of mass graves in London, not only sheds light on the darkest chapters of British history but also ignites a profound understanding of the tragedy, making a compelling case for why this documentary is a must-watch for anyone interested in the profound impacts of pandemics on human society.

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.

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.

It's not all about the pouches. These mammalian misfits are full of surprises, from flamboyant kangaroo showdowns to rattling koala mating calls. They might seem a bit bizarre but don't underestimate them. With unexpected superpowers and amazing adaptability, they have conquered a continent.

One extraordinary family of fish has achieved the ultimate form of gender equality. When it comes to breeding, seahorses do it like no other animal on the planet. Their fierce females refuse to be left holding the baby. So it's the males that carry their brood. In this episode we explore the world of mating seahorses which are the only animals in the world that have a major gender role reversal.