This episode covers the nature of how life may have developed on Earth and the possibility of life on other planets. Tyson begins by explaining how the human development of writing systems enabled the transfer of information through generations, describing how Princess Enheduanna ca. 2280 BCE would be one of the first to sign her name to her works, and how Gilgamesh collected stories, including that of Utnapishtim documenting a great flood comparable to the story of Noah's Ark. Tyson explains how DNA similarly records information to propagate life, and postulates theories of how DNA originated on Earth, including evolution from a shallow tide pool, or from the ejecta of meteor collisions from other planets. In the latter case, Tyson explains how comparing the composition of the Nakhla meteorite in 1911 to results collected by the Viking program demonstrated that material from Mars could transit to Earth, and the ability of some microbes to survive the harsh conditions of space. With the motions of solar systems through the galaxy over billions of years, life could conceivably propagate from planet to planet in the same manner. Tyson then moves on to consider if life on other planets could exist. He explains how Project Diana performed in the 1960s showed that radio waves are able to travel in space, and that all of humanity's broadcast signals continue to radiate into space from our planet. Tyson notes that projects have since looked for similar signals potentially emanating from other solar systems. Tyson then explains that the development and lifespan of extraterrestrial civilizations must be considered for such detection to be realized. He notes that civilizations can be wiped out by cosmic events like supernovae, natural disasters such as the Toba disaster, or even self-destruct through war or other means, making probability estimates difficult. Tyson describes how elliptical galaxies, in which some of the oldest red dwarf stars exist, would offer the best chance of finding established civilizations. Tyson concludes that human intelligence properly applied should allow our species to avoid such disasters and enable us to migrate beyond the Earth before the Sun's eventual transformation into a red giant.

More than a decade ago, scientists announced that they had produced the first draft of the human genome, the 3.6 billion letters of our genetic code. It was seen as one of the greatest scientific achievements of our age, a breakthrough that would usher in a new age of medicine. Find out how close we are to developing the life-changing treatments that were hoped for". Follow three people, each with a genetic disease, as they go behind the scenes at some of Britain's leading research labs to find out what the sequencing of the human genome has done for them - and the hope this remarkable project offers all of us.

Moscow, 31 December 1991: the Red Flag of the Kremlin is pulled down and replaced by the three-coloured banner of Russia, marking the end of the Soviet Union and of its ideologies. Illustrated with testimonies of top protagonists and Mikhail Gorbachev himself, the documentary recounts, day by day, the critical last two years that led to the fall of the largest and one of the most totalitarian empires of the 20th century.

Told by the activists and leaders who live and breathe this movement for justice, Whose Streets? is an unflinching look at the Ferguson uprising. When unarmed teenager Michael Brown is killed by police and left lying in the street for hours, it marks a breaking point for the residents of St. Louis, Missouri.
Grief, long-standing racial tensions and renewed anger bring residents together to hold vigil and protest this latest tragedy. Empowered parents, artists, and teachers from around the country come together as freedom fighters. As the national guard descends on Ferguson with military grade weaponry, these young community members become the torchbearers of a new resistance. Whose Streets? is a powerful battle cry from a generation fighting, not for their civil rights, but for the right to live.

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.

How does light escape from the sun? We take a journey from the center of the sun, following the path of light. We witness its fiery birth from in the core, its 430,000 mile battle against gravity and magnetism, and its escape from the solar surface.