In the extraordinary final chapter, viewers are taken on a global journey to review regions renowned for their extreme longevity. From picturesque Sardinia to the serene landscapes of Okinawa and the vibrant community in Loma Linda, the film uncovers the secrets behind these remarkable Blue Zones. It offers a fascinating glimpse into the unique lifestyles and community dynamics that contribute to the residents' exceptional health and long lives, leaving viewers intrigued by the possibilities of enhancing their own well-being.
The film doesn't stop at showcasing these remarkable places; it also delves into innovative approaches to improve public health. By highlighting initiatives like Singapore's Proximity Housing Grant and the transformative Blue Zones project, the episode encourages viewers to reflect on the impact of environment and policy on individual health. Ultimately, it leaves audiences pondering how they can adapt these life-enhancing principles to enrich their own lives.

Most people hope they'll live a long, healthy, and happy life, but few are able to travel the world in an attempt to reverse-engineer the formula for longevity. That's exactly what Dan Buettner did: Beginning in the early aughts, Buettner collaborated with National Geographic, scouring the globe in pursuit of places where people live much longer than average, and thus, the concept of 'Blue Zones' came to be.
In the first episode, how can people live so long and with such great health? A trip to Okinawa reveals simple secrets about diet, lifestyle and longevity. They maintain a sense of purpose no matter what age and you won't find them laying on the sofa.

The fifth programme explores the alliances formed between the animal and plant worlds. Attenborough dives into Australia's Great Barrier Reef and contrasts the nocturnal feeding of coral, on microscopic creatures, with its daytime diet of algae. Some acacias are protected by ants, which will defend their refuge from any predator. Besides accommodation, the guards are rewarded with nectar and, from certain species, protein for their larvae as well. Fungi feed on plants but can also provide essential nutriment to saplings (Mycorrhiza). The connection is never broken throughout a tree's life and a quarter of the sugars and starches produced in its leaves is channelled back to its fungal partners. Meanwhile, fungi that feed on dead wood leave a hollow trunk, which also benefits the tree. Orchids enjoy a similar affiliation. Lichens are the product of a relationship between fungi and a photosynthetic associate, usually algae. They are extremely slow-growing, and a graveyard is the perfect location to discover their exact longevity. Mistletoe is a hemiparasite that obtains its moisture from a host tree, while using own leaves to manufacture food. Its seeds are deposited on another by the mistletoe tyrannulet, following digestion of the fruit. The dodder (Cuscuta) is also parasitic, generally favouring nettles, and siphons its nourishment through periodic 'plugs' along its stem. The rafflesia has no stem or leaves and only emerges from its host in order to bloom — and it produces the largest single flower: one metre across.