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.

In the fourth episode of the series, Clovis was the first Frankish king to acknowledge the Christian faith. This changed the direction of Europe's history.

Graham-Dixon reveals how the north of the country has produced some of the most dazzling and iconic art of the modern age. Spain's turbulent history has shaped artists from Francisco Goya to Pablo Picasso. Graham-Dixon argues that Spanish architecture is the art form now taking the nation forward in the new millennium.

This episode examines the idea of scientific racism, an ideology invented during the 19th century that drew on now discredited practices such as phrenology and provided an ideological justification for racism and slavery. The episode shows how these theories ultimately led to eugenics and Nazi racial policies of the master race.

Examines the impact of racism in the 20th century. By 1900 European colonial expansion had reached deep into the heart of Africa. Under the rule of King Leopold II, the Belgian Congo was turned into a vast rubber plantation. Men, women and children who failed to gather their latex quotas would have their limbs dismembered. The country became the scene of one of the century's greatest racial genocides, as an estimated 10 million Africans perished under colonial rule.

Through the mountains and jungles of Colombia, Cooper goes in search of the truth behind one of the greatest stories ever told - the legend of El Dorado. His journey takes him from Bogota to the Caribbean coast, through territories once dominated by two cultures, the Muisca and the Tairona, who flourished for centuries before the arrival of the Spanish in the 16th century. Cooper reveals forgotten peoples who valued gold in a way the Western world still struggles to understand, travelling to an astonishing lost city and meeting the last survivors of an ancient civilisation.