Stonehenge is an icon of prehistoric British culture, an enigma that has seduced archaeologists and tourists for centuries. Why is it here? What is its significance? And which forces inspired its creators? Now a group of international archaeologists led by the University of Birmingham and the Ludwig Boltzman Institute in Vienna believe that a new state-of-the-art approach is the key to unlocking Stonehenge's secrets. For four years the team have surveyed and mapped every monument, both visible and invisible, across ten square kilometres of the sacred landscape to create the most complete digital picture of Stonehenge and the surrounding area over millennia. Known monuments have yielded more data than ever before, revealing hidden structures within, and new finds are revolutionising the very timeline of Stonehenge. The film takes the viewer on a prehistoric journey from 8000 BC to 2500 BC as the scientists uncover the very origins of Stonehenge, learning why this landscape is sacred, preserved and has been revered by following generations. Evidence of war and conflict, as well as the cultivation of ideas and industry, is explored to reveal complex communities with international trade links as far-reaching as Spain and central Europe.

For more than 80 years, Solenopsis Invicta has been on a ceaseless march across the United States, racking up six billion dollars every year in crop damage, equipment repair, and pest control. They have conquered more than 320 million acres in 13 states and killed at least 80 people. And the invader is still on the move. Globally. Now, scientists are cracking the ant's ancient secrets to success and breeding winged assassins to hunt them down. Stunning 3D macro photography explores the secret world of the fire ant and the cutting-edge research into stopping it

Professor Diarmaid MacCulloch - one of the world's leading historians - reveals the origins of Christianity and explores what it means to be a Christian. In the first episode, he overturns the familiar story that it all began when the apostle Paul took Christianity from Jerusalem to Rome. Instead, he shows that the true origins of Christianity lie further east, and that at one point it was poised to triumph in Asia, maybe even in China. The headquarters of Christianity might well have been Baghdad not Rome, and if that had happened then Western Christianity would have been very different.

Ant colonies are one of the wonders of nature - complex, organised and mysterious. This programme reveals the secret, underground world of the ant colony in a way that's never been seen before. At its heart is a massive, full-scale ant nest, specially designed and built to allow cameras to see its inner workings. The nest is a new home for a million-strong colony of leafcutter ants from Trinidad. For a month, entomologist Dr George McGavin and leafcutter expert Professor Adam Hart capture every aspect of the life of the colony, using time-lapse cameras, microscopes, microphones and radio tracking technology.

Is there anyone out there? Astronomers have been pointing their radio telescopes at the skies for decades trying to pick up alien signals, so far without success. But now there's a new way of looking for aliens. Hitch a ride with Dr Graham Philips as he joins astronomers trawling through the galaxy looking for signs of extra-terrestrial intelligence.

Could the fabled lost city of Atlantis have been located? Professor Freund explained how he led a pursuit to find the lost civilisation, believed by many to be an ancient Greek myth, by using deep-ground radar, digital mapping and satellite imagery. He contends that Atlantis, described by Plato in 360BC, in Spain's Donaña National Park, north of Cadiz, and was wiped out by a giant tsunami. Plato wrote it had been destroyed by a natural disaster in 9,000BC. Experts are now surveying marshlands in Spain to look for proof of the ancient city.