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.

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.

Each night, across the planet, our cities illuminate the darkness. Their lights burning brighter than ever before. And whilst we're asleep, animals are making the most of this new neon landscape. The sunset in Los Angeles, Chicago, and Toronto creates worlds of opportunities for the cleverest animals willing to take the risk.

The great mountain ranges are some of the planet's most spectacular landscapes, but they are unforgiving places to live in, and only a few animals have what it takes to live at extreme altitude. Mountain animals are amongst the most elusive in the world, and this film provides unique and intimate glimpses into their secretive lives. Witness the moment four snow leopards come together when a mother and cub become trapped between two rival males. Join grizzly bears as they dance against trees to rub off their winter fur and soar with golden eagles hunting amongst Europe's snow-capped peaks.

Cities are growing at a faster rate than any other habitat on Earth. They may seem an unlikely place for animals to thrive, but they can be a world of surprising opportunity. Leopards prowl the streets of Mumbai, peregrine falcons hunt amongst New York's skyscrapers, and a million starlings perform spectacular aerial dances over Rome. In Jodhpur, langurs are revered as religious deities and in Harar, locals live in harmony with wild hyenas. Many animals, however, struggle to cope in the urban jungle. As the architects of this environment, can humans choose to build cities that are homes for both them and wildlife?

Lesotho's Maseru Central Correctional Institute in Southern Africa holds the country's most dangerous and disturbed criminals. Shockingly almost half the inmates are doing time for rape. The culture of sexual violence in Lesotho has deep roots in society. Women are taken as secondary citizens in their culture. And sexual aggression continues inside the prison.
In this episode, Raphael Rowe will spend a week locked up in this African prison surrounded by sex offenders.