The big blue is the world's greatest wilderness, far from shore and many kilometres deep. It's a vast marine desert where there is little to eat and nowhere to hide. Yet it's home to some of the biggest and most spectacular creatures on earth. This episode reveals what it takes to survive in this savage and forbidding world. We witness feats of incredible endurance, moments of high drama and extraordinary acts of heart-wrenching self-sacrifice. Every animal in the big blue must find their own unique way to survive. Sperm whales have the largest brains in the world. They live for 80 years, and we are only now beginning to learn the extraordinary complexity of their language of clicks - thought to coordinate the whole family in everything from childcare to hunting. With special pressure-proof cameras, we witness record-breaking feats of endurance as they hunt for squid a kilometre down into the abyss. Only recently have we begun to solve the mystery of where baby turtles disappear to in their early years. They leave the crowded waters of the coast and head to the open ocean, where they use floating debris like logs as life rafts. Here they remain until adulthood, adrift on the high seas in relative safety away from coastal predators. Over half of all animals in the open ocean drift in currents. Jellyfish cross entire oceans feeding on whatever happens to tangle with their tentacles. The jelly-like Portuguese man-of-war can harness sail power to fish with its deadly tentacles. Sometimes there is a brief explosion of food in this marine desert, but ocean hunters must be fast to make the best of this bonanza. We witness super pods of up to 5,000 spinner dolphins racing to herd vast shoals of lanternfish, briefly caught at the surface where it is thought they spawn. New aerial footage reveals, for the first time, the truth to a centuries-old sailors' legend of the 'boiling seas' - the spectacular feeding frenzy of 90kg tuna and dolphins smashing through the lantern fish shoals turning the sea white with foam.

Supermassive black holes are the engines that power our universe and one of the major players in the evolution of galaxies. They're in fact the driving force at the heart of nearly every galaxy in the cosmos. Now, a new mystery has emerged about the oldest supermassive black holes. We see supermassive black holes in the very early universe. And we don't understand how they grew so large so quickly. We have clues about their formation but, can we solve the mystery of this supermassive growth spurt?

The Great Pyramid of Giza's construction is still shrouded in mystery, despite it being the only survivor among the Seven Wonders of the Ancient World. In Building the Great Pyramid, travel back 4,500 years with the BBC as they re-create the circumstances under which it may have been built, as well as the daily life of the population at that time. Expert archaeologists, Egyptologists, and scholars share their latest theories on what may have happened. The film combines dramatic reconstruction, location shooting and state-of-the-art CGI computer effects. Directed and written by Jonathan Stamp.

In the echoing chambers of a cave located in the Cradle of Humankind in South Africa, paleoanthropologist Lee Berger stumbles upon a revelation that could rewrite History. Not only has he uncovered the world's oldest graveyard, but it's also unlike anything we've ever seen. Amid the shadows, the faint glimmers of ancient hearths, mysterious tools and cryptic symbols hint at rituals beyond our understanding. A place where knowing what an ancient creature did means glimpsing into its very soul.
This isn't just any discovery - it's a journey into a world of human-level complexity in an entirely different species from our own. A tale that beckons with the allure of the unknown, challenging everything we thought we knew about hominid evolution and the origins of belief. A story so profound, it demands respect from the entire human race. Dive into the mystery and experience the awe, spirituality, and eerie wonders of the 'Cave of Bones'.

The last episode explores Mescaline, the psychoactive molecule in San Pedro and peyote cacti, a sacred medicine that Native Americans have had to fight for the right to use. At the Indigenous practices there's always an elder, someone who knows the territory very well, who's presiding. There's usually a group, a community is involved, There's always an intention, a purpose to what you're doing, and you're treating it as sacred, in order to achieve altered states of consciousness, which contribute to worship in various ways, or celebration or healing.
But maybe all this is not so new to Western culture after all. In the old Greek histories of Eleusis, people who were initiated there got the drink, the kykeon, and then they had the illumination. The precise recipe is a mystery, but we know that the kykeon was a psychoactive brew that was used at the Eleusinian mysteries, a sacred annual ritual of enlightenment practiced by some of the world's greatest minds including Socrates, Plato, and Aristotle. So why did this ritual come to an end more than 1,000 years ago? Was the possibility of illumination or achieving a higher consciousness considered threatening to the powers that be? Have the drug wars been merely an extension of that fear?
Psychedelics has a major part in how we can heal as a community, how we can heal as a city, and how we can heal as a country. The current renaissance of psychedelics could not come at a better time as the world confronts a crisis in mental health. But psychedelics have much to offer. The psychedelic experience changes the mind in ways that will help scientists better understand how it works. All these altered states allow us to probe what is the greatest mystery in all of nature. The emergence from mere matter of something as miraculous as consciousness. But an even bigger question is whether psychedelics might help us address the environmental crisis of how we think about our place in nature. One of the greatest gifts of psychedelics is how they reanimate the natural world, allowing us to perceive the subject, the spirit of all species, not just our own. And to feel a deeper sense of interconnectedness with nature.

Did China hide crucial information about Covid-19 from the world? What began with a handful of mystery pneumonia cases in Wuhan late last year has now left more than half a million dead worldwide. Beijing says it has been open and transparent throughout, but former BBC China Editor Carrie Gracie investigates how it delayed reporting the initial outbreak and evidence that Covid-19 could be spread by people. It also silenced doctors who tried to speak out.
The film also hears from one high-level insider who believes the animal market at the centre of the Wuhan outbreak should have been treated as a 'crime scene' and from experts who warn that this crisis may be a 'dress rehearsal' for an even more deadly pandemic in the future.