This episode tells the tale of what's broadly considered China's most creative dynasty - the Song (960-1279). Michael Wood heads to the city of Kaifeng, the greatest city in the world before the 19th century. Here in Twin Dragon Alley, locals tell him the legend of the baby boys who became emperors.
He explores the ideas and inventions that made the Song one of greatest eras in world culture, helped by China's most famous work of art, the Kaifeng scroll, which shows the life of the city in around 1120. A chef makes Michael a recipe from a Song cookbook, while a guide to 'how to live happy, healthy lives for old people', published in 1085 and still in print, is discussed with local women doing their morning exercises. The Song was also a great era for scientific advance in China. Michael steers a huge working replica of an astronomical clock, made by China's Leonardo da Vinci.
Then at a crunch Chinese Premier League match, Michael tells us the Chinese invented football! The golden age of the northern Song ended in 1127, when invaders sacked Kaifeng, but they survived in the south. At their new capital, Hangzhou, Wood joins locals dancing by the West Lake, while in the countryside he meets Mr Xie with his records of 40 generations of ancestors. The final defeat of the Song took place in a naval battle in the estuary of the Pearl River in 1279. When all was lost, rather than surrender to the Mongols, a loyal minister jumped into the sea with the young boy emperor in his arms. 'So ended the glory of the Song', Wood concludes, 'but a new age would arise... as in China, it always has!'.

Painted over five centuries ago, Filippo Lippi's nativity is like none other: it shows the birth of Christ in a dark, wooded wilderness. There are no shepherds, kings, ox, ass – there is no Joseph. Its beauty inspired Michelangelo, Leonardo da Vinci and Botticelli. But it also conceals a deeply personal story. It was painted for Cosimo de Medici, a wealthy banker who feared that his money was dragging him straight to hell. The artist's life was equally surprising. One of the most celebrated painters of his day, Filippo Lippi was also a Carmelite friar, but he was no stranger to the temptations of the flesh, to which he frequently yielded. Shortly before painting his Adoration, he caused uproar by seducing a twenty year-old nun. His paintings rejoice not only in divine beauty, but in the beauty of women. In later times, the Adoration's history was interwoven with that of rulers and dictators. It became a bargaining chip after Napoleon's allies seized twenty merchant ships. And in the 20th century, it was hidden by the Nazis in a potassium mine, where specialist american officers, known as Monuments Men, stumbled upon it. they were now told to get it ready to be shipped out. In an unprecedented turn of events they refused. This is the only known case in the whole of the Second World War of American officers refusing an order. It was sent to the National Gallery of Art, but in 1949 Lippi's Adoration was returned to Germany.

Ideas about time and space are explored in the changes that constellations undergo over time, the redshift and blue shift measured in interstellar objects, time dilation in Albert Einstein's theory of relativity, the designs of both Leonardo da Vinci and spacecraft that could travel near light speed, time travel and its hypothetical effects on human history, the origins of the Solar System, the history of life, and the immensity of space. In Cosmos Update, the idea of faster-than-light travel by wormholes (researched by Kip Thorne and shown in Sagan’s novel Contact) is discussed.

The story of how the secret of life has been examined through the prism of the most complex organism known - the human body. It begins with attempts to save the lives of gladiators in Ancient Rome, unfolds with the macabre work and near-perfect drawings of Leonardo in the Renaissance, through the idea of the 'life force' of electricity, to the microscopic world of the cell. It reveals how a moral crisis unleashed by work on the nuclear bomb helped trigger a great breakthrough in biology - understanding the structure and workings of DNA.