Narrated by Ewan McGregor, Humpback Whales is an extraordinary journey into the mysterious world of one of nature's most awe-inspiring marine mammals. Set in the spectacular waters of Alaska, Hawaii and the remote islands of Tonga, this ocean adventure offers audiences an up-close look at how these whales communicate, sing, feed, play and take care of their young. Humpbacks were nearly driven to extinction 50 years ago, but today are making a slow but remarkable recovery. Join a team of researchers as they unlock the secrets of the humpback and find out why humpbacks are the most acrobatic of all whales, why they sing their haunting songs, and why these intelligent 55-foot, 50-ton animals migrate up to 10,000 miles round-trip every year.

The open arenas of grassland and desert make up half of all land on our planet. In these exposed habitats, predators like cheetahs, bald eagles and lions can usually see their prey. But it works both ways: their prey can see them too. With nothing but open vistas, the element of surprise is hard-won, and predators must make their own opportunities.

A jaguar fights to keep his river home in Brazil as the night brings both challenges and opportunities to hunt. Evening is falling in the world's greatest tropical wetland, Brazil's Pantanal. A stronghold for South America's most secretive big cat, the jaguar. And enjoying the last warmth of the day is a male known as Juru. At six years old and weighing over 100 kilos, he's amongst the largest, most powerful big cats in the Americas. This prime stretch of river has been his territory for two years. But tonight Juru's reign hangs in the balance. In a recent fight with a rival male, he badly injured his paw. It's left him weak and hungry. The coming days and nights will test him more than ever before. He'll need to summon the strength to defend his river.

Deep in the twisted roots of a giant strangler fig tree, hidden from view, lives perhaps the most bizarre nighttime creature of all. The spectral tarsier, tiny primates barely larger than a tennis ball. As darkness falls, a family of these small primates in Sulawesi ventures into the jungle to find food while protecting their babies.

No two islands in the Galapagos are the same. The imperceptible drift of a continental plate keeps each island biologically isolated. David Attenborough explores this evolutionary crucible, encountering tortoises that weigh up to half a tonne, finches that use tools and lizards that communicate using press-ups; for Darwin, this was all evidence for his theory of evolution. We see the final footage of the world famous tortoise fondly known as Lonesome George, the last survivor of his species. David Attenborough was the last person to have ever filmed with him. Darwin’s famous visit had a downside – the arrival of man. David investigates the impact we’ve had in these islands, as our influence is a double-edged sword. We’ve disrupted the natural balance but he also believes Darwin would be thrilled with the advances we have made in science. We’re also now uncovering evidence that evolution is more rapid than Darwin could ever have imagined. Whatever wonders the Galapagos Islands hold today, they are only a hint of what awaits them in the future.

The Indians called the frozen peak of this great Alaskan mountain range Denali, or 'the high one.' Most know it as Mount McKinley. This preserved wilderness comes to life with the thaw of spring and wildlife abounds during the brief summer, only to succumb to the grip of the long winter. Watch as 5-week-old grizzly cubs play, a moose gives birth to her calf, and a wood frog survives the deep freeze of winter. Breath-taking shots of dazzling northern lights over vast and lush wilderness make this an unforgettable Eden.