In the third part of his journey into the history of Christianity, Professor Diarmaid MacCulloch charts Orthodoxy's extraordinary fight for survival. After its glory days in the eastern Roman Empire, it stood right in the path of Muslim expansion, suffered betrayal by crusading Catholics, was seized by the Russian tsars and faced near-extinction under Soviet communism. MacCulloch visits the greatest collection of early icons in the Sinai desert, a surviving relic of the iconoclastic crisis in Istanbul and Ivan the Terrible's cathedral in Moscow to discover the secret of Orthodoxy's endurance.

Political humorist and author Bill Maher travels around the globe interviewing people about God and religion. Known for his analytical skills, wit and commitment to never pulling a punch, Maher brings his characteristic honesty to an unusual spiritual journey.
Muslims, Jews and Christians of many kinds pass before his jaundiced eye. He goes to a Creationist Museum in Kentucky, which shows that dinosaurs and people lived at the same time 5000 years ago. Maher speaks to a rabbi in league with Holocaust deniers. He talks to a Muslim musician who preaches hatred of Jews. Maher finds the unlikeliest of believers and, in a certain Vatican priest, he even finds an unlikely skeptic.

Michael Wood tells the tale of China's first great international age under the Tang Dynasty (618-907). From the picturesque old city of Luoyang, he travels along the Silk Road to the bazaars of central Asia and into India on the track of the Chinese monk who brought Buddhism back to China. This tale is still loved by the Chinese today and is brought to life by storytellers, films and shadow puppet plays. Then in the backstreets and markets of Xi'an, Michael meets descendants of the traders from central Asia and Persia who came into China on the Silk Road. He talks to Chinese Muslims in the Great Mosque and across town hears the amazing story of the first reception of Christianity in 635. Moving south, Michael sees the beginnings of China as an economic giant. On the Grand Canal, a lock built in 605 still handles 800 barges every day! The film tracks the rise of the silk industry and the world's favourite drink - tea. Michael looks too at the spread of Chinese script, language and culture across east Asia. 'China's influence on the East was as profound as Rome on the Latin West', he says, 'and still is today'. Finally, the film tells the intense drama of the fall of the Tang. Among the eyewitnesses were China's greatest poets. In a secondary school in a dusty village, where the Chinese Shakespeare - Du Fu - is buried in the grounds, the pupils take Michael through one famous poem about loss and longing as the dynasty falls. And in that ordinary classroom, there is a sense of the amazing drama and the deep-rooted continuities of Chinese culture.

Professor Robert Bartlett explores the impact of the Normans on southern Europe and the Middle East. The Normans spread south in the 11th century, winning control of southern Italy and the island of Sicily. There they created their most prosperous kingdom, where Christianity and Islam co-existed in relative harmony and mutual tolerance. It became a great centre of medieval culture and learning. But events in the Middle East provoked the more aggressive side of the Norman character. In 1095, the Normans enthusiastically answered the Pope's call for holy war against Islam and joined the first crusade. They lay siege to Jerusalem and eventually helped win back the holy city from the muslims. This bloody conquest left a deep rift between Christianity and Islam which is still being felt to this day.

The Queen of Sheba - an exotic and mysterious woman of power - is immortalised in the world's great religious works, among them the Hebrew Bible and the Muslim Koran. She also appears in Turkish and Persian painting, in Kabbalistic treatises, and in medieval Christian mystical works, where she is viewed as the embodiment of Divine Wisdom and a foreteller of the cult of the Holy Cross. In Africa and Arabia her tale is still told to this day and, indeed, her tale has been told and retold in many lands for nearly 3,000 years.

The publication of Salman Rushdie's novel The Satanic Verses in 1988 sparked a culture war in Britain between those in the Muslim community, who considered the book blasphemous and called for the book to be banned, and those defending it as an expression of freedom of speech. Protests, which began in the north of England, soon spread across the UK and to the rest of the Islamic world, culminating in February 1989 with Iran's Ayatollah Khomeini issuing a fatwa - a death sentence on the writer.
Now, 30 years on, broadcaster and journalist Mobeen Azhar embarks on a journey, starting in his native Yorkshire where the protest first began, to examine the lasting effect the book has had on the Muslim community and how the events of 1989 continue to have an impact today.