Diarmaid MacCulloch's own life story makes him a symbol of a distinctive feature about Western Christianity - scepticism, a tendency to doubt which has transformed both Western culture and Christianity. In the final programme in the series, he asks where that change came from. He challenges the simplistic notion that faith in Christianity has steadily ebbed away before the relentless advance of science, reason and progress, and shows instead how the tide of faith perversely flows back in. Despite the attacks of Newton, Voltaire, the French Revolutionaries and Darwin, Christianity has shown a remarkable resilience. The greatest damage to Christianity was actually inflicted to its moral credibility by the two great wars of the 20th century and by its entanglement with Fascism and Nazism. And yet it is during crisis that the Church has rediscovered deep and enduring truths about itself, which may even be a clue to its future.

In this mind-bending series, Professor Jim Al-Khalili explores the vast range of size in the universe, from tiny atoms to gigantic, interconnected galaxies.
In the first episode, Jim will enter the world of objects that are too tiny to glimpse with the naked eye. Starting with the smallest insects, he moves on to encounter living cells with amazing superpowers and confronts some of humanity's deadliest enemies in the form of viruses. Going smaller still, he encounters wondrous new nanomaterials such as graphene, discovered by physicist Andre Geim. These are revolutionising engineering, medicine, computing, electronics and environmental science. Finally, Jim comes face to face with the fundamental building blocks of the world around us – atoms – and reveals why understanding the science of the 'small' is crucial to the future of humanity.

Can new emission-free electric planes replace our polluting airliners and revolutionize personal transportation in our cities? The film takes a ride in some quiet, energy-efficient, prototypes that are vying for success as electric flight takes off.
The race is on to stop the climate emergency and we're seeing more and more people really paying attention to their carbon footprint. Aviation is a fast-growing offender, but is it too slow to respond. Could rapid progress in electric technology change the equation?

The State Hermitage Museum in St Petersburg is one of the largest and most visited museums in the world. Margy Kinmonth's film tells the story of its journey from imperial palace to state museum, investigating remarkable tales of dedication, devotion, ownership and ultimate sacrifice, showing how the collection came about, how it survived tumultuous revolutionary times and what makes the Hermitage unique today. Holding over three million objects and boasting more curators than any other museum, the Hermitage's story is Russia's history in microcosm and its art has lived to tell the tale

Dr Aleks Krotoski concludes her investigation of how the World Wide Web is transforming almost every aspect of our lives. Joined by Facebook founder Mark Zuckerberg, Bill Gates, Al Gore and the neuroscientist Susan Greenfield, Aleks examines the popularity of social networks such as Facebook and asks how they are changing our relationships. And, in a ground-breaking test at University College London, Aleks investigates how the Web may be distracting and overloading our brains.

Our lifespan is increasing by 2.5 years every decade - and a third of all babies born today can expect to live to 100. But living longer can come at a cost. Old age itself brings with it a range of debilitating illnesses, many of which are the result of accumulating damage during our lifetime. Three diseases in particular have become the main killers in the developed world - cancer, heart disease and dementia. But a revolution in bio-medicine is now offering new hope for the treatment of these ailments, and the potential to extend our lives still further. Methods such as gene editing and stem cell therapies are transforming the way medicine can conquer disease today. "How to Live Longer" counts with the guide of the Nobel laureate Sir Paul Nurse, for whom the big question isn't just what science can do to fix our bodies and extend our lives, but whether it's right to use all the tools and techniques available.