As tides rise and fall twice a day, vast amounts of water swirl around the earth. This is a huge energy source that's currently largely untapped. An estimated 3000 gigawatts are available to be harvested globally, enough to power a third of the earth's homes. Yet compared to wind and solar, the technology needed to harness tidal power is still in its infancy. The power of the ocean’s tides is the last great untapped energy source on Earth. From sub-sea kites to floating platforms, teams of engineers are racing to perfect the technology to harness the vast flows of water.

Weather controls the distribution of freshwater on Earth. David Attenborough narrates how this uneven distribution has given rise to an incredible diversity of species and habits, from the driest desert to the lushest tropical rainforest. Featuring a colony of ants banding together into a raft every time its home in the Amazon floods, a rain frog that manages to eke out an existence in one of the world's driest habitats on Earth, and the last wild camels that survive the Gobi Desert's bitter winters by eating snow that blows in from Siberia.

The world's shipping industry is facing a major challenge. If global shipping were a country it would be the sixth largest producer of greenhouse gas emissions. At current growth rates, if we do nothing, those emissions could double or even triple by 2050. But shipping companies and engineers are creating remarkable new machines to make their industry greener, using a resource that has moved man across the world’s oceans for thousands of years…Wind.

A new force threatens our perfect planet. In the past, five mass extinction events were caused by cataclysmic volcanic eruptions. It was not the lava or ash that wiped out life, but an invisible gas released by volcanoes: carbon dioxide. Almost every part of modern life depends on energy created by burning fossil fuels, and this produces CO2 in huge amounts. Humans are changing our planet so rapidly, it’s affecting earth’s life support systems: our weather, our oceans and the living world. The greatest change to be made is in how we create energy, and the planet is brimming with natural power that can help us do just that. It’s these forces of nature - the wind, the sun, waves and geothermal energy - that hold the key to our future.
Through compelling animal-led stories and expert interviews, we discover how CO2 is destabilising our planet. We meet rescued orphaned elephants in Kenya, victims of ever worsening droughts, and join ocean patrols off the coast of Gabon fighting to save endangered sharks. In the Amazon, we witness wildlife teams saving animals in the shrinking forests, and in San Diego we enter a cryogenic zoo preserving the DNA of endangered species before they become extinct.

The pirates of the Caribbean's humble base in Nassau turns into a boomtown run by Benjamin Hornigold. But Hornigold's crew deposes him for his refusal to attack English ships; but one man, Edward Thatch, remains loyal. Meanwhile, pirate raids on British slaves provokes outrage.

The Caribbean is home to a notorious band of British pirates called the Flying Gang. They plunder merchant ships, sailing from the Americas to Europe and Africa. England's King George I has had enough, so he comes up with a shock tactic to end piracy. It's an offer from the King, a pardon, clemency for those who turn their backs on piracy. Those who refuse will be hunted down and hanged. Two pirates, Blackbeard and Charles Vane stand the King's man, Woodes Rogers. Who will win the final battle?