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.

From the frozen poles to the searing deserts, this episode shows how animals have come up with strategies to survive the uneven amounts of sunlight that fall on our planet over the course of a year. The exception is on the equator, where the duration of day and night remain the same throughout the year. Here, this guaranteed sunlight drives the great diversity of life in the tropical jungles.

Agnes Varda, one of the leading lights of France's honored French New Wave cinema era, and professional photographer and muralist, J.R., partake on a special art project. Together, they travel around France in a special box truck equipped as a portable photo booth and traveling printing facility as they take photographs of people around the country.
With that inspiration, they also create special colossal mural pictures of individuals, communities and places they want to honor and celebrate. Along the way, the old cinematic veteran and the young artistic idealist enjoy an odd friendship as they chat and explore their views on the world as only they can.

35 years after the Chernobyl disaster, Ben Fogle travels to the most radioactive place on Earth. He spends a week living alone inside the Chernobyl Exclusion Zone, gaining privileged access to the doomed Control Room 4 where the disaster first began to unfold.
'The planet faces unprecedented challenges - many of them, like Chernobyl, of our own making. What I've discovered in Chernobyl is that nature's reclaiming it. This is the greatest, accidental rewilding project of the globe. For me, the really exciting part of the Chernobyl story is the accidental hope that came from it. '

After ending 120 years of civil war and reunifying Japan under his banner, Toyotomi Hideyoshi, the supreme ruler of Japan, lays dead. In a desperate attempt to protect his dynasty, just before his death, Hideyoshi created a council of five powerful warlords. They are to govern Japan until his young son comes of age. But the power hungry Tokugawa Ieasyu declares war on those who oppose him.

In May 2009, NASA astronauts embark on a mission to perform maintenance and repairs to the Hubble Space Telescope. As they go about their tasks, danger and beauty are never far away. The nature of space indicates that even the simplest routine can go fatally awry, while amazing photographs taken by the telescope celebrate the wonder of Earth's celestial surroundings.
An IMAX 3D camera chronicled the effort of 7 astronauts aboard the Space Shuttle Atlantis to repair the Hubble Space Telescope.