Graham-Dixon journeys to the country’s scorched centre to explore Spanish art of the 16th and 17th centuries. From the mystical world of El Greco to the tender genius of Velazquez, this was a moment so extraordinary it became known as the Golden Age. But beneath the glittering surface was a dark and savage heart. Travelling from the architectural jewel of Toledo to majestic Madrid, Andrew Graham-Dixon traces the rise and fall of the Spanish Empire, the brutal conquest of the New World, and the religious madness of the Inquisition, to discover how a history so violent could produce some of the most beautiful art ever seen.

This episode provides an overview of the nature of electromagnetism, as discovered through the work of Michael Faraday. Tyson explains how the idea of another force of nature, similar to gravitational forces, had been postulated by Isaac Newton before. Tyson continues on Faraday, coming from poor beginnings, would end up becoming interested in studying electricity after reading books and seeing lectures by Humphry Davy at the Royal Institution. Davy would hire Faraday after seeing extensive notes he had taken to act as his secretary and lab assistant. After Davy and chemist William Hyde Wollaston unsuccessfully tried to build on Hans Christian Ørsted's discovery of the electromagnetic phenomena to harness the ability to create motion from electricity, Faraday was able to create his own device to create the first electric motor by applying electricity aligned along a magnet. Davy, bitter over Faraday's breakthrough, put Faraday on the task of improving the quality of high-quality optical glass, preventing Faraday from continuing his research. Faraday, undeterred, continued to work in the Royal Institution, and created the Christmas Lectures designed to teach science to children. Following Davy's death, Faraday returned to full time efforts studying electromagnetism, creating the first electrical generator by inserting a magnet in a coil of wires. Tyson continues to note that despite losing some of his mental capacity, Faraday concluded that electricity and magnetism were connected by unseen fields, and postulated that light may also be tied to these forces. Using a sample of the optical glass that Davy had him make, Faraday discovered that an applied magnetic field could affect the polarization of light passing through the glass sample (a dielectric material), leading to what is called the Faraday effect and connecting these three forces. Faraday postulated that these fields existed across the planet, which would later by called Earth's magnetic field generated by the rotating molten iron inner core, as well as the phenomena that caused the planets to rotate around the sun. Faraday's work was initially rejected by the scientific community due to his lack of mathematical support, but James Clerk Maxwell would later come to rework Faraday's theories into the Maxwell's equations that validated Faraday's theories. Their combined efforts created the basis of science that drives the principles of modern communications today.

In this final episode, Mary Beard delves even deeper into ordinary Roman life by going behind the closed doors of their homes. She meets an extraordinary cast of characters - drunken housewives, teenage brides, bullied children and runaway slaves - and paints a more dynamic, lusty picture of Roman family life. Mary uncovers their preserved beds, furniture and cradles, tries on Roman wedding rings and meets some eccentric wives like Glyconis, praised by her husband for liking a drink or two, and Allia Potestas, who lived in a Roman menage a trois. Mary explores Roman parenting, childbirth and children, including Sulpicius Maximus, an 11-year-old schoolboy who was worked to death by his pushy parents, and Geminia Mater, a 5-year-old tomboy. Finally, Mary paints a more nuanced picture of Roman slavery and asks why if it was such a brutal institution did many Romans choose to be buried with their servants - living cheek by jowl in death, as in life

Richard Dawkins deals with some of the philosophical and social ramifications of the theory of evolution. Dawkins starts out in Kenya, speaking with palaeontologist Richard Leakey. He then visits Christ is the Answer Ministries, Kenya's largest Pentecostal church, to interview Bishop Bonifes Adoyo. Adoyo has led the movement to press Kenya's national museum to sideline its collection of hominid bones pointing to man's evolution from ape to human.[5] The collection includes the Turkana Boy discovered by Kamoya Kimeu, a member of a team led by Richard Leakey in 1984. Dawkins discusses social darwinism and eugenics, explaining how these are not versions of natural selection, and that 'Darwin has been wrongly tainted'. He then meets with evolutionary psychologist Steven Pinker to discuss how morals can be compatible with natural selection. He goes on to explaining sexual selection, with peafowls as an example. To find out whether sexual selection plays a role for altruism and kindness among humans, he visits women who are looking for sperm donors, as well as a sperm bank manager. Dawkins also explains kin selection and selfish genes.

Travelling from K2 in Pakistan to Ladakh in India. It is a short distance as the crow flies but, due to politics, a huge loop. He passes through the Sikh city of Amritsar, with its Golden Temple, and through Shimla with its Vice Regal Lodge, Gaiety Theatre and cosy half-timbered tea-houses. He then meets the 14th Dalai Lama in Dharamsala, where the Tibetan government is in exile.

In the Land of the Cave Bear, Alice ventures to the parts of the northern hemisphere, hit hardest by the cold - Europe and Siberia. High in the mountains of Transylvania, a cave sealed for thousands of years reveals grisly evidence for a fight to the death between two staving giants, a cave bear and a cave lion. Yet Alice discovers that for woolly rhinos and woolly mammoths, the Ice Age created a bounty. The Mammoth Steppe, a vast tract of land which went half way round the world, provided food all year round, for those that liked the cold. It was these mammoths that Europe's most dangerous predators hunted for their survival.