Everything that lives on land, animal or plant, depends on fresh water. Yet only part of it is within reach: Much of the planet's fresh water, is locked away, almost two-thirds of it lies frozen around the poles. Even away from the poles, much of the land's fresh water freezes each winter. The need for fresh water is as strong as ever. However, the supply is becoming increasingly unpredictable and uncertain for all manner of species. We are not alone in our need for water, but we have the ability to ensure the fresh waters of the world do flow, and we alone can determine how they are shared.

More than 90% of all crashes have a human driver as the cause. So if you want to solve traffic fatalities, the best solution is driverless vehicles. It's an ambitious goal, but only possible because of the recent breakthroughs in deep learning. Artificial intelligence is one of those key pieces that has made it possible now to do driverless cars where it wasn't possible ten years ago. For computers, until very, very recently, to do even the most basic visual tasks, like seeing a picture of a person and knowing that it's a person was remarkably hard. That's obviously fundamental to being able to understand the world around you with the sensors that you have. And we've made also gigantic strides in being able to perform complex tasks.

After years of anticipation, autonomous vehicles are now being tested on public roads around the world. As ambitious innovators race to develop what they see as the next high-tech pot of gold, some experts warn there are still daunting challenges ahead, including how to train artificial intelligence to be better than humans at making life-and-death decisions.
How do self-driving cars work? How close are we to large-scale deployment of them? And will we ever be able to trust AI with our lives?

This episode tells the tale of what's broadly considered China's most creative dynasty - the Song (960-1279). Michael Wood heads to the city of Kaifeng, the greatest city in the world before the 19th century. Here in Twin Dragon Alley, locals tell him the legend of the baby boys who became emperors.
He explores the ideas and inventions that made the Song one of greatest eras in world culture, helped by China's most famous work of art, the Kaifeng scroll, which shows the life of the city in around 1120. A chef makes Michael a recipe from a Song cookbook, while a guide to 'how to live happy, healthy lives for old people', published in 1085 and still in print, is discussed with local women doing their morning exercises. The Song was also a great era for scientific advance in China. Michael steers a huge working replica of an astronomical clock, made by China's Leonardo da Vinci.
Then at a crunch Chinese Premier League match, Michael tells us the Chinese invented football! The golden age of the northern Song ended in 1127, when invaders sacked Kaifeng, but they survived in the south. At their new capital, Hangzhou, Wood joins locals dancing by the West Lake, while in the countryside he meets Mr Xie with his records of 40 generations of ancestors. The final defeat of the Song took place in a naval battle in the estuary of the Pearl River in 1279. When all was lost, rather than surrender to the Mongols, a loyal minister jumped into the sea with the young boy emperor in his arms. 'So ended the glory of the Song', Wood concludes, 'but a new age would arise... as in China, it always has!'.

Michael Wood embarks on a great historical adventure, exploring the stories, people and landscapes that have helped create China's distinctive character and genius over four thousand years. Is the history of the world's newest superpower, from its ancient past to the present day.
Starting in Wuxi, Michael joins the Qin family reunion, when 300 relatives gather to worship their ancestors on Tomb Sweeping Day. 'Like the nation, the family has been through so much,' one says. 'Now everyone wants to know - what are our roots?'
Looking for the origins of the Chinese state, he visits the excavations at Erlitou and sees an exquisite turquoise dragon sceptre from 2000 BC. China's first writing is found on 'oracle bones' dug up from the Shang royal tombs at Anyang in the 1920s. At the Beijing Planetarium, Michael travels back in time as astronomers plot the planetary conjunction that the ancients believed foretold the overthrow of the Shang Dynasty. Next, the Age of Philosophers and Confucius, whose book Analects has had greater influence worldwide than even the Bible, according to some. In Xi'an, we hear how the First Emperor united China and created the authoritarian Qin state that gave us the word China. Finally, Michael returns to the temple fair in Henan for a dramatic night ceremony to give thanks to the ancestors. China, Michael concludes, is rising again, not just because of its economic strength, but because of the incredible solidarity of the Han Chinese view of their own civilisation, their sense of family and, of course, the presence of the ancestors.

Zachary Quinto sets out to research the strangest creatures dug up from the depths of the ocean and to see how much they lend to the monsters that are depicted in myth and legend. Starting in Australia, he meets with a teenager who was savagely attacked by a swarm of mysterious flesh-eating monsters, only to jump into the water himself the next day amongst highly venomous sea creatures.
From the carnivorous fish of American rivers to the eyeless monsters of the Atlantic Ocean, Zachary finds some merit in these old monster stories and is starting to understand just what we mean when we say that we know less than 1% of what waits in the depths below.