Brian travels across the US and encounters some astonishing creatures that reveal how the senses evolved. It is a story that takes him through life's journey, from single-celled organisms to sentient beings.

During 1959-1961 both the Americans and Soviets are planning manned space flight, and we see both sides preparing to do so with the development of the Vostok programme (Russia) and Project Mercury (USA). After difficulties and failures on both sides, the Soviets succeed in putting Yuri Gagarin into space first, with the Americans putting Alan Shepard up shortly afterwards.

Dr Michael Scott looks at the dramatic decline of Athens and the remarkable triumph and transformation of theatre. During the 4th century BC Athens would lose its Empire, its influence and even its democracy. But theatre, that most Athenian of inventions, would thrive, spreading throughout the Greek world and beyond and giving rise to a new kind of comedy, one so popular and prevalent that it is still at the heart of our comedy today.

Electricity is not just something that creates heat and light, it connects the world through networks and broadcasting. After centuries of man's experiments with electricity, the final episode tells the story of how a new age of real understanding dawned - how we discovered electric fields and electromagnetic waves. Today we can hardly imagine life without electricity - it defines our era. As our understanding of it has increased so has our reliance upon it, and today we are on the brink of a new breakthrough, because if we can understand the secret of electrical superconductivity, we could once again transform the world.

The Internet promises us escape from reality. We can go places we never thought possible and express ourselves as never before. But as we sit in our homes surrounded by screens, are we free... and safe? In this episode meet a woman pulled into an online cult from the safety of her bedroom; a former pilot who suffers from Electromagnetic Hypersensitivity and can only find relief in the absence of electricity and wifi; plus, a quadriplegic who uses cutting-edge adaptive robotics and virtual reality to transcend his body's limitations.

Documentary telling the little-known story of how Darwin came to write his great masterpiece, On the Origin of Species, a book which explains the wonderful variety of the natural world as emerging out of death and the struggle of life. In the twenty years he took to develop a brilliant idea into a revolutionary book, Darwin went through a personal struggle every bit as turbulent as that of the natural world he observed. Fortunately, he left us an extraordinary record of his brilliant insights, observations of nature, and touching expressions of love and affection for those around him. He also wrote frank accounts of family tragedies, physical illnesses and moments of self-doubt, as he laboured towards publication of the book that would change the way we see the world.