Professor Marcus du Sautoy explores why we are driven to measure and quantify the world around us and why we have reduced the universe to just a handful of fundamental units of measurement. He tells the story of the metre and the second - how an astonishing journey across revolutionary France gave birth to the metre, and how scientists today are continuing to redefine the measurement of time and length, with extraordinary results.

Alice Roberts explores the latest discoveries in the study of human origins, revealing the transformation that has been brought about in this field by genetics. Traditional Palaeoanthropology, based on fossils, is being transformed by advanced genome sequencing techniques. We now know that there were at least four other distinct species of human on the planet at the same time as us - some of them identified from astonishingly well-preserved DNA extracted from 50,000-year-old bones, others hinted at by archaic sections of DNA hidden in our modern genome. What's more, we now know that our ancestors met and interacted with these other humans, in ways that still have ramifications today. Alice uses these revelations to update our picture of the human family tree.

Japan's landscapes range from snowy mountains to subtropical warmth. They are full of wildlife - and animals' and people's lives often cross as they adapt to these extremes. The central island of Honshu is home to over 100 million people, and its biggest city, Tokyo, is one of the largest urban metropolises on earth. But it has a wild heart - most of Honshu is mountainous. This wilderness is home to an astonishing range of wildlife - black bears, monkeys, exquisite fireflies and even cow demons. But all across this island, from the mountains to the edge of the sea, people and nature are drawn together in the most unexpected ways.

Since 2010, Artificial Intelligence is revolutionized by deep learning, neural networks that discern complex patterns in huge quantities of data and react in real time. A.I. is a primal force, like fire. The same fire that warms us can incinerate our homes; A.I. could enslave mankind -- or, join us in a grand alliance to reach the stars.

Richard Feynman is one of the most iconic, influential and inspiring scientists of the 20th century. He helped design the atomic bomb, solved the mystery of the Challenger Shuttle catastrophe and won a Nobel Prize. 25 years after his death - in his own words and those of his friends and family - this is the story of the most captivating communicator in the history of science.

Every year, over a thousand climbers try to reach the summit of Mount Everest, with the annual record for successful attempts currently standing at 633. But of that number, nearly half were Sherpas - the mountain's unsung heroes. Yet the Sherpa community has remained secretive about their nation, culture and experiences living in the shadow of the world's highest mountain. Now, for the first time, they open the door into their world. Without the expertise of the Sherpas, only the hardiest and most skilful climbers would succeed. Every day they risk their lives for the safety of others, yet they seek neither glory nor reward, preferring to stay in the background. Following the stories of four such Sherpas - Phurba, Ngima, Ngima Tenji and Gelu - this film reveals the reality of their daily lives, not just up the mountain, but with their families after they return home.