The next great voyage of human exploration has already begun: the search for life on planets orbiting distant stars. With extraordinary CGI, the world's most inspiring scientists, via extreme environments on Earth and around the solar system, the film takes viewers aboard the next generation of space ships, across the cosmos and beneath the clouds of the exo-planets to discover The Living Universe.
Part 1: 'The Planet Hunters' For as long as we’ve had eyes to see and minds to wonder we’ve marveled at the stars. Since the discovery of the first so-called exoplanet in 1994, the Planet Hunters have transformed the way we see the universe. It is the year 2157, and spacecraft Artemis enters the final phase of construction.

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.

The Great Pyramids of Giza remain one of the enduring wonders of the ancient world. This mesmerizing monument have eluded astronomers and archeologists for centuries. Why and how the ancient pyramids of the pharaohs were built? Were they merely burial tombs, or a cosmic vehicle to the celestial world? What were the motives and methods behind the orientation of the pyramids to face the four cardinal directions with extreme accuracy?
The world's renowned Egyptologists, astronomers and engineers join forces to solve some of the long-held mysteries about the pyramids.

Gaby Roslin and Amir Khan present a program in which they apply the latest science to some of the worst sleepers. They include an extreme snorer, a man who suffers from night terrors, a woman who has restless leg syndrome, and a man with chronic insomnia for 20 years.
The film also shows a sleep deprivation experiment to test for risky behaviour, pain resistance and emotional control. When the subjects reach the final hours of the challenge, the experiment begins to take its toll as the participants' emotions go into overdrive, with one threatening to quit altogether.

The Search for Freedom is the story of a cultural revolution fueled by the human desire to live in the moment and do what makes you feel the most alive. DIrector Jon Long presents this visceral look at the pioneers of extreme sports, including skateboarder Danny Way and motobiker Robbie Madison, and the human stories behind their search for thrills.

Silk is the invertebrates' great invention, used in a range of ways from from the protective stalks of lacewing eggs to the amazing hanging threads of New Zealand's 'glow worms'. Spiders, though, have taken silk-spinning to extremes. The common wolf spider has no web, but the female is a gentle parent, encasing her eggs in silk and carrying the precious bundle wherever she goes. The bolas spider uses a ball of sticky silk soaked in a copy of moth pheromone to lure its prey. Millions of communal spiders live and feed together in a vast, towering web - an arachnophobe's nightmare.