Dr. Thomas Asbridge introduces the epic story of the Crusades – a tale of religious fanaticism and unspeakable brutality, of medieval knights and Jihadi warriors; of castles and kings; of heroism, betrayal, and sacrifice. He explains how, using fresh evidence, eye-witness testimonies and contemporary accounts – from both the Christian and Islamic worlds – we are able to re-examine this epic medieval drama, and how he has retraced the steps of the Crusaders from a small town in France to the magnificent cities of the Holy Land, bringing to life the human experience of the Crusades, and shedding new light on how it was that two of the world’s great religions waged war in the name of God.

In ‘Why Do I Need You?’ Dr. David Eagleman explores how the human brain relies on other brains to thrive and survive. Our fundamentally social nature can hold the key to our sucdess as a species. Our brains are so fundamentally wired to interact that we are something more like a single vast super-organism. In this age of digital connection, we desperately need to understand how human brains interact if we want our civilization to have a future, if we want to avoid fanaticism and to embrace cooperation. This neural interdependence begins at birth. Dr. David Eagleman invites a group of babies to a puppet show to showcase their ability to discern who is trustworthy, and who isn’t.

Atheist and scientist Richard Dawkins visits England, America and Israel interveiwing prominant people of faith; Islamic, Hasidic Jews, and the new Christian sects popping up throughout the world, and expressing his view of the extent to which this fanaticism has degraded our civilisation, and will continue to degrade it. "The God Delusion" explores the unproven beliefs that are treated as factual by many religions and the extremes to which some followers have taken them. Dawkins opens the programme by describing the "would-be murderers ... who want to kill you and me, and themselves, because they're motivated by what they think is the highest ideal." Dawkins argues that "the process of non-thinking called faith" is not a way of understanding the world, but instead stands in fundamental opposition to modern science and the scientific method, and is divisive and dangerous.