Beneath the modern city streets, ancient underground neighbourhoods and sewerage systems reveal the technological marvels that helped advance an empire.

From 1987 to the early 1990s, Florida was inundated with UFO sightings, while 90 miles away at Guantanamo Bay, USOs (Unidentified Submerged Objects) were seen rising out of the ocean.

Throughout the world, ancient rites and rituals are believed to connect humans to another dimension. But just who - or what - are we communicating with?

...Of Stolen Art: 2012. The search of a flat in Munich, owned by elderly recluse, Cornelius Gurlitt, reveals how Gurlitt�s part-Jewish father, Hildebrand, struck a deal with the devil � and became an art dealer for Adolf Hitler.

Humanity's first volcanic hyper eruption blows through the Earth's surface. Shockwaves and molten rock destroy buildings and cities. Then as volcanic gas blocks out sunlight, food chains collapse, and epic famine threatens the very future of mankind.

Battles BC

With a single slingshot to the head, young David defeated the giant Goliath. But behind this famous tale lies a world of treachery, intrigue and political ambition.

Evolve

A look at communication as a key tool for survival, from simple bacteria cooperating to take down creatures a million times their size, to mankind's complex systems of interaction.

Engineering an Empire

After the fall of Rome, autonomous city states emerged and revitalised their cities with new and radical designs. Explore how a new Italy was built.

Beneath the modern city streets, ancient underground neighbourhoods and sewerage systems reveal the technological marvels that helped advance an empire.

From 1987 to the early 1990s, Florida was inundated with UFO sightings, while 90 miles away at Guantanamo Bay, USOs (Unidentified Submerged Objects) were seen rising out of the ocean.

Throughout the world, ancient rites and rituals are believed to connect humans to another dimension. But just who - or what - are we communicating with?

...Of Stolen Art: 2012. The search of a flat in Munich, owned by elderly recluse, Cornelius Gurlitt, reveals how Gurlitt�s part-Jewish father, Hildebrand, struck a deal with the devil � and became an art dealer for Adolf Hitler.

Humanity's first volcanic hyper eruption blows through the Earth's surface. Shockwaves and molten rock destroy buildings and cities. Then as volcanic gas blocks out sunlight, food chains collapse, and epic famine threatens the very future of mankind.

Battles BC

With a single slingshot to the head, young David defeated the giant Goliath. But behind this famous tale lies a world of treachery, intrigue and political ambition.

Evolve

A look at communication as a key tool for survival, from simple bacteria cooperating to take down creatures a million times their size, to mankind's complex systems of interaction.

Engineering an Empire

After the fall of Rome, autonomous city states emerged and revitalised their cities with new and radical designs. Explore how a new Italy was built.

Beneath the modern city streets, ancient underground neighbourhoods and sewerage systems reveal the technological marvels that helped advance an empire.

From 1987 to the early 1990s, Florida was inundated with UFO sightings, while 90 miles away at Guantanamo Bay, USOs (Unidentified Submerged Objects) were seen rising out of the ocean.

Throughout the world, ancient rites and rituals are believed to connect humans to another dimension. But just who - or what - are we communicating with?

...Of Stolen Art: 2012. The search of a flat in Munich, owned by elderly recluse, Cornelius Gurlitt, reveals how Gurlitt�s part-Jewish father, Hildebrand, struck a deal with the devil � and became an art dealer for Adolf Hitler.

Humanity's first volcanic hyper eruption blows through the Earth's surface. Shockwaves and molten rock destroy buildings and cities. Then as volcanic gas blocks out sunlight, food chains collapse, and epic famine threatens the very future of mankind.

Battles BC

With a single slingshot to the head, young David defeated the giant Goliath. But behind this famous tale lies a world of treachery, intrigue and political ambition.

Evolve

How did flying creatures come to be? From the first vertebrates to take a flight to the creatures that have conquered the sky, examine the animals which have evolved to fly.

In less than 200 years, the Aztecs went from a tribe of nomads into the most powerful civilisation the New World had ever known. How did they achieve such greatness?

From plague victims being buried alive to body snatchers, illegal distilleries and castle dungeons, Edinburgh's underground world has a myriad of stories to tell.

The team examines the most compelling examples of UFO relics available, including a unique and other-worldly piece of metal in Missouri.

Might the tools and technology of ancient builders have come from distant galaxies? If the ancient builders did use advanced technology, could it prove that aliens visited Earth thousands of years ago?

Missing In Alaska

In 1950, a military transport plane vanished in the Alaska Triangle with 44 people on board, and hasn't been seen since. Was its disappearance caused by bad weather or something more sinister?

Plants are used for food, medicine and clothing, to build our world and change how we feel - and they have played a vital role in our evolution.

Tools and machines have allowed us to overcome our physical limitations, but they are also transforming what it means to be human.

Mother Nature unleashes a barrage of attacks around the globe. In San Francisco, an earthquake crushes commuters; a rolling avalanche devours climbers in the Himalayas; and in Nebraska, lightning strikes an unlucky storm chaser.