In a far cry from the steamy jungles of Rwanda or the icy waters of the Arctic, British naturalist Sir David Attenborough has donned a necktie and met with US president Barack Obama to discuss climate change and the future of the planet. The two met at the White House — a place the naturalist had never yet explored — on Sir David's 89th birthday in May to film the interview". It was the first time the respected wildlife filmmaker had met an American president and he seemed a little awed by the experience. Mr Obama, who grew up watching Sir David's programs, seemed equally thrilled. The president has the environment and climate change on his radar and is anxious to see progress made as his presidency comes to a close. He faces stiff opposition from Republicans in Congress on his plans to tackle climate change, but remains determined to make changes before leaving office. "I don't have much patience for anyone who denies that this challenge is real," he said. "We don't have time for a meeting of the Flat Earth Society." Sir David, who has been called "the godfather of natural history TV" by the BBC, brought to the meeting six decades dedicated to sharing the wonders of the natural world with television audiences. After initially being rejected for television because his teeth were deemed "too big", Sir David went on to make his Life on Earth television series, which has been watched by more than 500 million people worldwide. His name is now synonymous with nature, conservation and wildlife. During the television interview, the men discussed global warming, renewable energy and how children and young people hold the key to reversing the damage.

In episode two, we discover the golden age of the La Tene Celtic warrior and reveal how their world extended as far as central Turkey. But by the middle of the first century BC, the Celts were under threat from an expanding Roman Empire, and the Gallic warrior Vercingetorix would challenge Julius Caesar in an epic battle that would shape the future of Europe.

This documentary attempts to make history by finding the lost city of Atlantis once and for all. Adventurer-geologist Dr. Martin Pepper sets out to prove his theory – that the true Atlantis existed on the Greek island of Santorini, and was destroyed in the biggest volcanic eruption in human history". In order to achieve his goal, Pepper will use new scientific evidence gathered using state-of-the-art sonar scans of the sea bed and microscopic analysis of the ancient landscape. One of the challenges he faces is that he must also match Santorini to a series of key clues embedded in the first ever description of Atlantis by the Greek philosopher Plato – from the lost city’s strange ring-shaped design, to the role Egyptian priests played in recording the legend in the first place. His journey will take him across the Mediterranean and out into the Atlantic Ocean. By the end of the program, he reveals the stunning findings which may pinpoint the city and show exactly what it looked like.

Scientific advancements are challenging the concept of what it means to be human. Technology embedded in our bodies is fairly common: artificial limbs, pacemakers. But new research is taking us beyond replacement parts and into a new realm that is changing the nature of the human body and the human mind. Will the fusion of biology and technology change how we think, how we feel, how we experience the world?

In the annals of Hollywood film since the artistic glories of the New Hollywood era, few have a better reputation and body of work in the field of suspense films exploring the contemporary darkness in American life than Brian De Palma. Here, the great film writer and director takes, us in his own words, through his professional life and a career that redefined film horror and suspense. All the while, he also confesses the challenges of working in Hollywood and the price even the great artists pay for being a part of it.

The contests between predators and prey are the most dramatic events in nature. Taking an intimate and detailed look at the remarkable strategies employed by hunters to catch their prey and the hunted to escape. Sir David Attenborough narrates. "The Hardest Challenge" reveals the extraordinary range of techniques predators use to catch their prey - from a leopard using all its powers of stealth to stalk impala in broad daylight to wild dogs, whose tactic is to wear down their prey over long distances; from Nile crocodiles, the planet's most patient predators, to killer whales who use teamwork and intelligence to take on humpback whales. But even with these finely tuned strategies, the outcome is far from certain. Surprisingly, most predators fail most of the time.