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 every ocean… just beyond our shores…lives an animal with characteristics we think of as ‘human’ – intelligent, social, curious, gentle, and fierce. They build cities, use tools, and collaborate with other species to hunt. They have personalities – some are bold, while others shy. These animals can change their skin colour, texture, and body shape in a blink of an eye and see in wavelengths beyond our vision. Recent studies reveal octopuses’ consciousness, sophisticated decision-making, and unique personalities. On tropical reefs, in frigid waters, from the shoreline to the deep sea and everywhere in between, the octopus have made a home. Join us as we reveal ‘Secrets of the Octopus’.
In the first chapter, whether transforming their body shape and color to disappear or mimicking their deadliest enemy, Octopus use shape-shifting superpowers to survive.

The second episode dives deeper into the enigmatic world of octopuses, uncovering the extraordinary intelligence of these cephalopods. From their ability to change color and shape in an instant to their sophisticated use of tools, this documentary reveals how octopuses navigate and survive in the ocean's most challenging environments. The documentary explores the profound cognitive abilities of octopuses, highlighting their potential for future planning, problem-solving, and even dreaming.
Witness the coconut octopus's ingenious stilt-walking and shell-wielding tactics, and marvel at the giant Pacific octopus's intricate hunting strategies. Through stunning underwater footage and insights from leading scientists like Dr. Alex Schnell and Dr. C.E. O'Brien, viewers are invited to rethink what they know about intelligence in the animal kingdom. This captivating film showcases the remarkable adaptability and creativity of octopuses, making it a must-watch for anyone fascinated by the mysteries of the ocean.