The Celts - one of the world's most mysterious ancient people. In Britain and Ireland, we are never far from our Celtic past but in this series Prof. Alice Roberts and archaeologist Neil Oliver travel much further afield, discovering the origins and beliefs of these Iron Age people in artefacts and human remains right across Europe, from Turkey to Portugal. What emerges is not a wild people on the western fringes of Europe, but a highly sophisticated tribal culture that influenced vast areas of the ancient world - and even Rome". Rich with vivid drama reconstruction, we recreate this pivotal time and meet some of our most famous ancient leaders - from Queen Boudicca to Julius Caesar - and relive the battles they fought for the heart and soul of Europe. Alice and Neil discover that these key battles between the Celts and the Romans over the best part of 500 years constituted a fight for two very different forms of civilisation - a fight that came to define the world we live in today. In the first episode, we see the origins of the Celts in the Alps of central Europe and relive the moment of first contact with the Romans in a pitched battle just north of Rome - a battle that the Celts won and that left the imperial city devastated.

The concept of a digital, decentralized currency is questioning things and the answers being spilled out are deep-seated, long-standing propositions that place a magnifying glass onto the seemingly untouchable financial institutions at the base of modern commerce. What may be uncovered in the philosophical, political, and economic questions could have radical implications for the rest of the 21st century". The documenteray ushers us in, not to explore simply Bitcoin, but to hint at the basis of trade, commerce, and civil society. Director Torsten's story of money is one filled with promise like a sunrise over a landscape of human spirit.

In 2014, the International Space Station had to move three times to avoid lethal chunks of space debris and there is an increasing problem of satellites mysteriously breaking down. With first-hand accounts from astronauts and experts, know the scale of the problem of space junk. Our planet is surrounded by hundreds of millions of pieces of junk moving at 17,000 miles per hour. Now the US government is investing a billion dollars to track them, and companies around the world are developing ways to clear up their mess - from robot arms to nets and harpoons. Learn the science behind the hit film Gravity and discovers the reality is far more worrying than the Hollywood fiction.

A documentary-horror film exploring the phenomenon of 'Sleep Paralysis' through the eyes of eight very different people. These people often find themselves trapped between the sleeping and waking worlds, totally unable to move but aware of their surroundings while being subject to frequently disturbing sights and sounds. A strange element to these visions is that despite the fact that they know nothing of one another, many see similar ghostly 'shadow men.' This is one of many reasons many people insist this is more than just a sleep disorder". This documentary digs deep into not only the particulars of these eight people's uncanny experiences, but it also explores their search to understand what they've gone through and how it's changed their lives. Directed by Rodney Ascher, he chose to focus on sleep paralysis as it had happened to him in the past. The film's crew initially began approaching participants via message groups, videos and a half dozen books that had been written.

This absolutely beautiful documentary on our World, its mystical beauty and miracles including slow motion footage of nature, animals, seasons, new life and daily beauties I've never seen nor imagined existed. The photography is sensational. The animal behaviour shown is incredible, beautiful and humorous. Even if you never have been a fan of nature documentaries, this blew you away

The digital era gives rise to unprecedented opportunity to exploit, and be exploited. Troves of child pornography are available at the click of a mouse. Who are these children - and who profits from their abuse? While facilitating the darker side of our impulses, technology is also being touted as a cure to rehabilitate predators. In this episode meet the children who are forced to perform sex acts on camera; people who use the same technology to protect kids and nab the perpetrators; plus, a pedophile who reveals the roots of his addiction.