This episode focuses on the Jurassic period, a time when the first giant killers stalked the Earth and lurked in the seas; a time when the slightest advantage meant the difference between life and death. In North America the iconic allosaurus, an ambush hunter with a lethal bite, dominated. Not even the heavily-armoured stegosaurus was safe from this killer, and incredible evidence reveals a glimpse of a vicious battle between these two giants. Life in Jurassic oceans was no easier; in 2008, a fossil was dug out of a frozen island high in the Arctic. It was a colossal marine reptile, twice as big as most ocean predators, at 15 metres long and weighing about 45 tonnes. This was Predator X. Its skull alone was nearly twice the size of a tyrannosaurus rex's, and its bite force unmatched by anything in the Jurassic seas. The balance of power between predator and prey is a fine one, as prey continually evolves different ways to avoid predators. But for the most successful and enduring predators, the battle to survive has always been tipped in their favour

Human Planet is a majestic portrait of humankind and the power of nature in extraordinary symbiosis, struggle and strife. For the first time, the camera has turned on ourselves. In doing so, we see how amazing human beings can be and how we adapt to any habitat, anywhere. Human Planet is epic in ambition, extreme in content, intimate in effect. It explores how we have devised ways of surviving in every corner of Earth – from the remotest deserts to the busiest urban metropolis. Each episode focuses on an iconic environment and reveals how we have adapted to the challenges of the landscape and the endless diversity of animals and plants we live with. Discover how our remarkable intelligence, tool use, and close-knit social lives have enabled us to cope with just about anything nature can throw at us". As an air-breathing animal, the human is not built to survive in water. But people have found ways to live an almost aquatic life so they can exploit the sea's riches. From a 'shark-whisperer' in the Pacific to Brazilian fishermen collaborating with dolphins to catch mullet, this journey into the blue reveals astonishing tales of ingenuity and bravery. Daredevil Galician barnacle-collectors defy death on the rocks for a catch worth 200 pounds per kilo. In Indonesia an epic whale-hunt, using traditional hand-made boats and harpoons, brings in a sperm whale. The Bajau 'sea gypsies' of the Sulu Sea spend so much time on water they get 'land sick' when they set foot on the land! We dive 40 metres down to the dangerous world of the Pa-aling fishermen, where dozens of young men, breathing air through a tangled web of pipes attached to a diesel engine, capture thousands of fish in a vast net. We see how surfing has its origins in the ancient beliefs of the ocean-loving Polynesians, and we join a Borneo free-diving spear-fisherman on a breath-taking journey 20 metres down in search of supper.

Rivers provide the essentials of life: fresh food and water. They often provide natural highways and enable us to live in just about every environment on Earth. But rivers can also flood, freeze or disappear altogether!Cities - Surviving the Urban Jungle Human Planet joins Sam Niang, a Laotian fisherman, as he walks a high wire strung above the raging Mekong River rapids on an extraordinary commute to work. There's also a look at the remarkable partnership between Samburu tribesmen and wild elephants in their search for water in the dried-out river beds of Northern Kenya. Plus, a father who must take his two children on a six-day trek down a frozen river - the most dangerous school run on Earth, and the ice dam busters of Ottowa with their dynamite solution to a city centre hold-up.

Earth may seem like the most hospitable planet in the solar system. But look again. Startling new discoveries reveal the blue planet has been plagued by more chaos and destruction than scientists once imagined. Stand on the Earth billions of years ago as a primitive planet called Theia slams into it. Shiver as our entire globe is frozen over like a gigantic snowball. Feel the heat as mammoth volcanoes scorch the landscape and darken the sky. From a cosmic gamma ray burst frying away the ozone layer to an Everest-size asteroid slamming into the ocean, we'll reveal new information about how these unparalleled events drove life to the brink of total extinction. Out of this continuous devastation, how has our planet--and life--got to where it is today? Are the worst days behind us--or lurking in the distant future?

In the last few years, the Red Planet has yielded up many new clues that life may have once existed there...and may even exist there today. There is now have proof that water once flowed on the surface, that Mars once had lakes, and that the frozen poles are mostly water, not carbon dioxide as previously thought. Mars has snow--an aurora--and lightning generated by dust storms. Most intriguing of all are the seasonal plumes of methane that just may point to bacteria living below the surface.

Drazen Petrovic and Vlade Divac were two friends who grew up together sharing the common bond of basketball. Together, they lifted the Yugoslavian National team to unimaginable heights. After conquering Europe, they both went to America where they became the first two foreign players to attain NBA stardom. But with the fall of the Soviet Union on Christmas Day 1991, Yugoslavia split up. A war broke out between Petrovic's Croatia and Divac's Serbia. Long buried ethnic tensions surfaced. And these two men, once brothers, were now on opposite sides of a deadly civil war. As Petrovic and Divac continued to face each other on the basketball courts of the NBA, no words passed between the two. Then, on the fateful night of June 7, 1993, Drazen Petrovic was killed in an auto accident. "Once Brothers" will tell the gripping tale of these two men, how circumstances beyond their control tore apart their friendship, and whether Divac has ever come to terms with the death of a friend before they had a chance to reconcile.