Could aliens have told Joan of Arc how to beat the English army? And could a US serviceman have received a message when he touched a spaceship? Experts investigate.

Lue Elizondo previously identified five observable characteristics of UFOs, dubbed the 'five observables'. But there is a so-called sixth observable Elizondo began to investigate - an invisible threat these craft may pose.

In 2008, witnesses in Needles, California, saw military helicopters carry away a glowing flying object. What was the government trying to hide? And could UFO clean-ups be common?

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, NM in 1947. What actually crashed there? The US government claimed it was a weather balloon. Others spoke of alien bodies, and government intimidation.

Did Viking explorers Erik the Red and Leif the Lucky make it all the way across the Atlantic to America 500 years before Columbus? Josh Bernstein sails a Viking ship from Denmark to discover what made the Vikings such masterful mariners.

The list of military eyewitnesses describing strange and threatening unidentified craft in U.S airspace is growing. And now, a U.S. Navy radar operator has provided something more: actual coordinates where UFOS appeared and disappeared.

The Laginas are astounded to learn that on a trip to Arizona, Gary Drayton may have gotten to the bottom of one the biggest treasure mysteries, one that has resulted in countless deaths and disappearance for those obsessed with finding it.

A miraculous meteorite falling from the heavens. A priceless gemstone with a deadly curse. And a chunk of sandstone considered so sacred that wars have been fought to protect it. What is it about stones that inspires some people to worship them?

Could aliens have told Joan of Arc how to beat the English army? And could a US serviceman have received a message when he touched a spaceship? Experts investigate.

Lue Elizondo previously identified five observable characteristics of UFOs, dubbed the 'five observables'. But there is a so-called sixth observable Elizondo began to investigate - an invisible threat these craft may pose.

In 2008, witnesses in Needles, California, saw military helicopters carry away a glowing flying object. What was the government trying to hide? And could UFO clean-ups be common?

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, NM in 1947. What actually crashed there? The US government claimed it was a weather balloon. Others spoke of alien bodies, and government intimidation.

Did Viking explorers Erik the Red and Leif the Lucky make it all the way across the Atlantic to America 500 years before Columbus? Josh Bernstein sails a Viking ship from Denmark to discover what made the Vikings such masterful mariners.

The list of military eyewitnesses describing strange and threatening unidentified craft in U.S airspace is growing. And now, a U.S. Navy radar operator has provided something more: actual coordinates where UFOS appeared and disappeared.

The Laginas are astounded to learn that on a trip to Arizona, Gary Drayton may have gotten to the bottom of one the biggest treasure mysteries, one that has resulted in countless deaths and disappearance for those obsessed with finding it.

A miraculous meteorite falling from the heavens. A priceless gemstone with a deadly curse. And a chunk of sandstone considered so sacred that wars have been fought to protect it. What is it about stones that inspires some people to worship them?

Could aliens have told Joan of Arc how to beat the English army? And could a US serviceman have received a message when he touched a spaceship? Experts investigate.

Lue Elizondo previously identified five observable characteristics of UFOs, dubbed the 'five observables'. But there is a so-called sixth observable Elizondo began to investigate - an invisible threat these craft may pose.

In 2008, witnesses in Needles, California, saw military helicopters carry away a glowing flying object. What was the government trying to hide? And could UFO clean-ups be common?

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, NM in 1947. What actually crashed there? The US government claimed it was a weather balloon. Others spoke of alien bodies, and government intimidation.

Hannibal's merciless attacks on Roman soil deal a near fatal blow to the future Empire. Sworn to a blood oath, Hannibal of Carthage does the unthinkable, marching 40 war elephants and an army over the Alps to gain the element of surprise.

Evidence continues to mount and patterns emerge, as a group of former U.S. government insiders seek the truth behind UFOs. A shocking new encounter pulls them to another part of the U.S.A. where two more military eyewitnesses risk their career.

Rick and Marty's good friend and world class wreck diver, John Chatterton, heads south to search for a never-recovered Spanish ship off the coast of Florida, and Gary Drayton shares with the brothers his most compelling, and valuable, find ever.

A dog that can detect cancer faster than doctors using sophisticated equipment. A horse that can read your mind. And birds that can sense disaster days before it happens. What gives animals these extraordinary powers?

During World War II, rumours spread that an aircraft had been built from extraterrestrial blueprints. Were aliens helping Hitler's quest for world domination?

Now, two and a half thousand years later, we restore Athens to its former glory, we re-create impregnable fortifications; the first senate house; experience the power of the Greek navy; and rebuild one of the most advanced water systems in the world.

Innovations in engineering including locomotives, sewer systems and a technologically superior navy aided the spread of the British Empire and shaped the modern world.

Examining ancient machines used in the large-scale engineering projects of the ancient world, particularly in Greece and Egypt. Included: machines used to transport 3-ton limestone coffins in Greece. Also: the building of the Parthenon.

Hannibal's merciless attacks on Roman soil deal a near fatal blow to the future Empire. Sworn to a blood oath, Hannibal of Carthage does the unthinkable, marching 40 war elephants and an army over the Alps to gain the element of surprise.

Evidence continues to mount and patterns emerge, as a group of former U.S. government insiders seek the truth behind UFOs. A shocking new encounter pulls them to another part of the U.S.A. where two more military eyewitnesses risk their career.

Rick and Marty's good friend and world class wreck diver, John Chatterton, heads south to search for a never-recovered Spanish ship off the coast of Florida, and Gary Drayton shares with the brothers his most compelling, and valuable, find ever.

A dog that can detect cancer faster than doctors using sophisticated equipment. A horse that can read your mind. And birds that can sense disaster days before it happens. What gives animals these extraordinary powers?