Most planets we know of are so hellish, it seems impossible that anything could live. But it's amazing where life can take hold in the Earth. Astrobiologists look for simple single-celled microbes known as extremophiles in places as Danakil Depression, known in Ethiopia as 'The Gateway to Hell.'
In Episode 2, the fictional world is Janus, a planet in such a close orbit than its rotation is locked by the star's gravity and it always shows the same face to its sun. On one side of the planet, it's always daytime, a searing desert. On the other side, it's forever night, a frozen shadowland. Squeezed between the two, a sliver of perpetual twilight. Freezing meltwater flows from the cold side, carving canyons through the landscape. Deep in these canyons lives an extraordinary five-legged creature.

The 1950's - the iconic Scuderia Ferrari battle to stay on top in one of the deadliest decades in motor racing history. Cars and drivers were pushed to their limits, and the competition for the world championship meant racing on a knife edge where one mistake could take a life. At the centre of it all was Enzo Ferrari, a towering figure in motor racing who was driven to win at any cost.
Amidst the stiff competition within his Ferrari team, two of its British stars, Peter Collins and Mike Hawthorn, put friendship first and the championship second. Ferrari: Race to Immortality tells the story of the loves and losses, triumphs and tragedy of Ferrari's most celebrated drivers in an era where they lived la dolce vita during the week and it was win or die on any given Sunday.

Someday, I will die. But should I? If I was offered a longer life, I would take that in a second. But how long is too long? Is death something I should deny forever, or is death and the role it plays in the universe something I am better off accepting?

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.

Space colonization is no longer the fodder of science fiction, it is becoming a reality. Examine the efforts underway to establish a human colony on Mars, including how they plan to grow food, recycle wastewater and introduce greenhouse gases to revive the red planet and make it more habitable for humans. Cutting-edge computer graphics are used to bring the universe down to earth to show what life would be like on Mars, and to imagine what kind of life forms might evolve in alien atmospheres.

Genetic breakthroughs have shed light on how life evolves in real-time. From filling in the missing links to creating a new species, in the last 50 years scientists have solved some of the biggest mysteries of evolution. In this episode, we look at revolutionary discoveries that shook the world and may shape our future.