Immense shoals of fish throng our shallow seas. Small fish, in turn, sustain bigger ones. The rich coastal seas are the fishing grounds of our planet and can provide an abundance of food for wildlife and humanity. The seas fringing land make up less than a tenth of the world's oceans but 90 percent of marine creatures live in coastal waters, from fearsome sharks to lowly urchins. Protecting these habitats is a battle humanity must win.

In the last 50 years, we have doubled the amount of fish we consume. Globally, billions of people rely on seafood as their primary source of protein. But the oceans can't keep up with so much demand. Around the world, fish stocks have plummeted and fisheries are crashing. People lost out. There was an industry just completely ravaged.
As the global fish supply dwindles, the industry faces a crisis on all sides - including crooked moguls, dubious imports and divisive regulations.

From space, Earth is a kaleidoscope. Turquoise plankton blooms trigger a feeding frenzy, China turns yellow with rapeseed flowers, and mysterious green lights appear in the ocean. Satellites give us a new perspective on its greatest and most beautiful spectacles allowing us to make new discoveries We can watch landscapes change through the seasons and marvel in the scale of their transformations.
Satellite cameras capture a kaleidoscope of extraordinary colours surprising and constantly changing, created by natural phenomena, by animals and by people. These colours are revealing new insight into the health of our fragile planet, transforming our understanding of our colourful home.

At 11 o'clock on New Year's Eve of the Cosmic Calendar, Homo erectus stood up for the first time, freeing its hands and earning the species its name. They began to move around, to explore, daring to risk everything to get to unknown places. Our Neanderthal relatives lived much as we did and did many of the things we consider to be 'human.' More restless than their cousins the Neanderthals and Denisovans, our Homo sapiens ancestors crossed seas and unforgiving landscapes, changing the land, ocean and atmosphere, leading to mass extinction. The scientific community gave our age a new name, 'Anthropocene.'
Since the first civilizations we've wondered if there's something about human nature that contains the seeds of our destruction. Syukuro Manabe was born in rural Japan and took an intense interest in Earth's average global temperature. In the 1960's, he would assemble the evidence he needed to predict the increase of Earth's temperature due to greenhouse gases until it becomes an uninhabitable and toxic environment, leading to our extinction. 'This doesn't have to be,' says Neil deGrasse Tyson, 'it's not too late. There's another hallway, another future we can still have; we'll find a way.'

Attenborough's journey continues in Canada's Rocky Mountains, where fossils document an explosion in animal diversity never seen before or since. Travelling from there to North Africa, the rainforests of Australia and the east coast of Scotland, Attenborough discovers how animals evolved to conquer not only the oceans but also the land and air. These remote and fascinating creatures are brought to life as never before with the help of cutting-edge scientific technology and photorealistic visual effects. From the first large predators to the first legs on land, these were creatures that evolved the traits and tools that allow all animals, including ourselves, to survive to this day.

Carl Sagan opens the program with a description of the cosmos and the Spaceship of the Imagination. The ship journeys through the universe's hundred billion galaxies, the Local Group, the Andromeda Galaxy, the Milky Way, the Orion Nebula, our Solar System, and finally the planet Earth. Eratosthenes' successful calculation of the circumference of Earth leads to a description of the ancient Library of Alexandria. Finally, the Ages of Science are described, before pulling back to the full span of the Cosmic Calendar.