Why do we sleep? And what does sleep have to do with memory, trauma, and our emotions? From fruit flies to whales, virtually every animal sleeps. But why? Why do we need to spend nearly a third of our lives in such a defenseless state? Scientists are peering more deeply into the sleeping brain than ever before, discovering just how powerful sleep can be, playing a role in everything from memory retention and emotional regulation to removing waste from our brains. So why are we getting so little of it?

Over billions of years, planet Earth has become home to an amazing interdependent ecosystem, containing a dizzying variety of animals and plants. But how did life here begin? And does it exist anywhere outside of our solar system? We uncover the secrets of our world by tracking the evolution of the cosmos itself, from the Big Bang onwards. Follow scientists responsible for some of the major breakthroughs in understanding the origins of life and witness how their discoveries are fundamentally changing the way we perceive the universe.

We are the generation of human beings that are going to know whether or not we're alone in the universe. This episode explores the search of exoplanets, from ancient Greek philosophers to the discoveries made possible with the Kepler Telescope. Unbelievable new worlds, planets made of diamond, planets of raining glass, worlds in collision, some plunging into stars, and others that just might harbor life.
Thanks to today's planet hunters, our views of the universe and of our place in it are undergoing one of the greatest revolutions in scientific history.

The fake story of the art found beneath the depths of the ocean from a 2,000 year old ship wreck. Damien Hirst and the crew recount the moments various discoveries are made, the myths and legends surrounding the find.

They defined music and popular culture like no other band ever will - but how did The Beatles make the journey from Merseyside teenagers to international pop stars in the 1960s? Made on Merseyside - The Beatles discovers how American rock 'n' roll and rhythm and blues dragged post-war Liverpool into one of the most vibrant music cities ever with the Mersey Sound.
Featuring revealing interviews from those involved in the early years of The Beatles in Liverpool and Hamburg and unique archive, the incredible story of The Beatles' previous band formations and why it took so long for them to achieve success makes riveting viewing. From school bands, to colleges; Hamburg to The Cavern Club, The Beatles changed the world of pop music forever, but was Pete Best's sacking from the band and Ringo's replacement the final part of the jigsaw?

Frequent security expos feature companies like Megvii and its facial- recognition technology. They show off cameras with A.I. that can track cars, and identify individuals by face, or just by the way they walk. In China it's been projected that over 600 million cameras will be deployed by 2020. Here, they may be used to discourage jaywalking, but they also serve to remind people that the state is watching. Matching with the most advanced artificial intelligence algorithm, they can actually use this data, real-time data, to pick up a face or pick up a action.
A.I. is a technology that can be used for good and for evil. So, how do governments limit themselves in, on the one hand, using this A.I. technology and the database to maintain a safe environment for its citizens, but not to encroach on a individual's rights and privacies?