Episode 3 delves into how life began on a roiling, violent Earth and explores the story behind Victor Goldschmidt, the man who found the first clues to life's beginnings on our planet. Neil deGrasse Tyson takes viewers on a journey through space and time to witness the tenacity and creativity of life on Earth and the prospects of life throughout the universe.

In 335 BC Alexander of Macedonia set off on an expedition to conqueror the world. The voyage of Alexander the Great covered more than 22,000 miles in ten years, from Greece to India and back, through some of the most difficult and unforgiving terrain. Michael Wood was hot on his trail, following, as closely as possible, in the footsteps of Alexander and the army that he drove to achieve the impossible. In this programme: the Lebanese city of Tyre, scene of Alexander's most desperate battle; the Palestinian legend of `Two-Horned Alexander'; and the Egyptian oasis of Siwa, where Alexander was proclaimed pharaoh and son of God.

After filming for three years, Planet Earth finally captures the shy Mongolian gazelle. Only a handful of people have witnessed its annual migration. Don't miss the bizarre-looking Tibetan fox, captured on film for the first time. Over six weeks the team follow a pride of 30 lions as they attempt to hunt elephants. Using the latest night vision equipment, the crew film the chaotic battles that ensue at close quarters.

Visit the ghostly villages surrounding Chernobyl (abandoned by humans after the 1986 nuclear disaster), travel to remote islands off the coast of Maine to search for abandoned towns that have vanished from view in only a few decades, then head beneath the streets of New York to see how subway tunnels may become watery canals. A visual journey, LIFE AFTER PEOPLE is a thought provoking adventure that combines movie-quality visual effects with insights from experts in the fields of engineering, botany, ecology, biology, geology, climatology, and archaeology to demonstrate how the very landscape of our planet will change in our absence.

This entertaining and engaging, high quality documentary film explores one of the most significant unanswered questions of our time 'Does infinity exist?' and if so, what are the implications of an infinite universe. If our universe is infinite, then what is the likelihood of other life? Could there be other civilizations just like ours or is it possible that we are the only intelligent life anywhere in our vast and likely infinite universe? Conversations with leading thinkers from multiple disciplines reveal the latest in scientific research, in this engaging and visually stunning film.

The first second of the Universe, the creation of everything when space, time, matter and energy burst into existence. It is the most important second in history, which seals the Universe's fate and defines everything that comes after - including us.