Series concludes with the focus shifting to the United States in the post-war years of the 1950s and beyond. Beginning with arguably the most notorious work of 20th century classical music, John Cage's 'silent' composition 4'33", it looks at how a series of maverick Americans re-invented the sound of classical music into a more simple form, bringing back harmonies and rhythms that made it increasingly popular with audiences across the world. It also examines how this music found its way into a spiritual realm, with the strain of pared-down religious composition that came to be known as 'holy minimalism'. From the Maverick concert hall in Woodstock, New York to an Orthodox cathedral in Estonia to a car park in Peckham, south London, the story is told by a stellar line-up of contributors including Philip Glass, Steve Reich, John Adams, Arvo Pärt and John Tavener.

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?

Professor Brian Cox concludes his exploration of our place in the universe by asking what next for the ape that went to space. Our future is far from certain. In Florida, Brian joins the latest efforts to protect Earth from potential catastrophic events. He joins a team of Nasa astronauts who are training for a future mission to an asteroid - should we ever discover one coming our way - under 30 feet of water in a submerged laboratory that simulates space. It is just one example of how, for our long-term survival, space exploration may well be vital. It is a view shared by Apollo 16 astronaut Charlie Duke, who tells Brian what it was like to escape the confines of the planet. It is a dream that both Nasa and now commercial companies share as they race to get humans back into deep space.
But space travel, like every leap our civilisation has ever made, requires energy. Here too, scientists are hard at work attempting to safeguard our future. At the National Ignition Facility in California, Brian witnesses the world's most successful fusion experiment in action. He believes that if their mission succeeds, our civilisation will have unlocked a way to the stars that will not destroy the planet in the process. Brian concludes by returning to the top of the world in Svalbard, where he gains access to our civilisation's greatest treasure, locked away in a vault buried deep in the permafrost.

What if you could combat aging and discover the full potential of the human body? Global movie star Chris Hemsworth, despite being in peak superhero-condition, is on a personal mission to learn how to stay young, healthy, strong, and resilient. Undergoing a series of epic trials and extraordinary challenges in order to understand the limits of the human body, he'll learn firsthand how we can live better for longer by discovering ways to regenerate damage, maximize strength, build resilience, supercharge memory and confront mortality.
Ever since his teenage years, stress has been part of Chris’s life, and he wants to learn how to deal with it better. Psychologist Modupe Akinola challenges him to stay calm during a terrifying walk along a crane that’s projecting out from the roof of a skyscraper. Modupe will train Chris in powerful physical and psychological techniques we can use to control the stress in our lives and combat the risk it poses to long-term health.

It is a nightmare that has stalked us for centuries: hordes of human beings transformed into mindless, cannibalistic monsters. Could this civilization-ending nightmare become reality? Scientists have discovered pathogens that turn insects into the walking dead. New strains of viruses are attacking humans every day. Mathematicians have calculated the likelihood of surviving a zombie virus outbreak: they’re not hopeful. Now neuroscientists are discovering how easy it is for us to lose conscious control of our bodies. Are we at risk of becoming puppets? If we were in the middle of a zombie apocalypse, would we even know it?

Troop withdrawals begin as the Americans train their ARVN allies to take over the war. Gery Benedetti patrols the hostile waters of the Mekong Delta. James Anderson leads a battalion into Cambodia after Nixon's controversial order. Don DeVore struggles to survive a fierce night attack, and Anne Purcell gets promising news about her husband.