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.

Hunger at Sea follows blue whales, sharks, sea lions, frigatebirds, dolphins and albatrosses to reveal the strategies they use to hunt for prey in the big blue. The open ocean is an immense wilderness that covers more than half the surface of our planet, yet for the most part it's a watery desert, largely devoid of life. Predators face an endless search to find and catch food, yet these great tracts of ocean are home to some of the most remarkable hunters on the planet.

The coast is the dynamic border between land and sea; powered by the tides and thrashed by waves, this is a world of continuous change. Opportunities never last long here, so hunters are always in a race against time. The coast is the only place on the planet where predators from air, land and sea come together. Dolphins that leave the safety of the sea to fish, walking octopuses, ingenious monkeys, fishing wolves and the greatest gathering of feeding humpback whales come to the coast to hunt. For all, timing is everything.

The final episode of the series visits the frontline of the conflict with the world's top predators, meeting the scientists fighting to save them. Crossing five continents and combining landmark natural history footage with real-life human drama, it checks the pulse of the earth's iconic animals, including lions, tigers, polar bears and blue whales. With three-quarters of the planet's carnivores now in decline, can people find ways to live with predators before they disappear forever?

In this series, the pursuit of the perfect image takes five adventurous photographers on journeys to the ends of the Earth, where they push the limits of their craft. In the first episode, Australian marine photographer Darren Jew captures mating humpback whales in Tonga, a 70-year-old biplane wreck and an active New Guinea volcano.

The film centers on our ongoing mission to explore and come to terms with the Arctic, and the compelling stories of our many forays into this captivating place will be interwoven to create a unifying message about the state of the Arctic today. Underlying all these tales is the crucial role that ice plays in the northern environment and the changes that are quickly overtaking the people and animals who have adapted to this land of ice and snow.