We live under a billion unblinking eyes - a global surveillance system that solves crime and uncovers terrorist plots. But are we ready for a world without secrets - where not even our homes are off-limits and corporations know our every desire?

These scientists are part of a global race. It's been running for over a decade... to build a mythical machine, the holy grail of calculations - a quantum computer. Remarkably, first-generation quantum computers have started to appear. Indeed, earlier this year, Google bought one. The D-Wave 2.

Having explained the science behind global warming, and addressed the arguments of the climate change sceptics earlier in the series, Dr Iain Stewart concludes the series by looking at the biggest challenge now facing climate scientists - Just how can they predict exactly what changes global warming will bring?
It's a journey that takes him from early attempts to model the climate system with dishpans, to supercomputers, and to the frontline of climate research today: Greenland. Most worryingly he discovers that scientists are becoming increasingly concerned that their models are actually underestimating the speed of changes already underway.

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.

A.I. can be used in many ways that are very beneficial for society. But the current use of A.I. isn't necessarily aligned with the goals of building a better society, unfortunately. But, but we could change that. A.I. will be viewed as an age of enlightenment. Our children and their children will see A.I. as serendipity, that A.I. is here to liberate us from having to do routine jobs, and push us to do what we love, and push us to think what it means to be human. But what if humans mishandle this new power?

Here's a growing trend in artificial intelligence. Dating video games and other applications let users carry on virtual relationships with computerized girlfriends ranging from career women to Japanese schoolgirls. There's even something for the ladies. How soon will there be artificial intelligence of such complexity that protecting its well-being and rights becomes a serious political and social concern? In what year will there be an app or computer program or a device that you not only love but that possibly, within the realm of believability might actually love you ...back?