When Emperor Decius took control of the empire, he sought to restore the pagan gods. His reign saw persecution of Christians, before plague struck and the Goths invaded.

Budapest sits on top of an ancient secret. Follow Eric Geller as he uncovers a top secret WWII hospital and finds the source of the boiling healing water used by the Romans and the Turks in the caves beneath Budapest.

The team probes some of the largest sightings of alleged UFOs ever recorded over the English Channel, including two eerie bright yellow flat objects spotted by pilots in 2007.

Biblical texts describe winged creatures carrying messages from the heavens. But are angels merely the product of the imagination - or do they really exist?

Bob and John head to Northern Spain, where a declassified document shows Hitler could have moved there from Denmark. They discover several eye witnesses, a satellite of the Third Reich, and what could be a Nazi communications center.

A mysterious email leads to what could be a huge underwater UFO base off the California coast. An investigation of new activity at Area 51 takes a dangerous turn. Plus, could an alien satellite be orbiting the Earth right now?

In Hamiltons possession is a wooden chest stuffed full of relics from medieval Christian pilgrimages. These include clamshell pendants from the Camino De Santiago in Spain and Jerusalem crosses from the Holy Land.

New York is one of the most man-made spaces on the planet, but everything from the height of its skyscrapers to the position of its harbour is governed by extraordinary forces.

When Emperor Decius took control of the empire, he sought to restore the pagan gods. His reign saw persecution of Christians, before plague struck and the Goths invaded.

Budapest sits on top of an ancient secret. Follow Eric Geller as he uncovers a top secret WWII hospital and finds the source of the boiling healing water used by the Romans and the Turks in the caves beneath Budapest.

The team probes some of the largest sightings of alleged UFOs ever recorded over the English Channel, including two eerie bright yellow flat objects spotted by pilots in 2007.

Biblical texts describe winged creatures carrying messages from the heavens. But are angels merely the product of the imagination - or do they really exist?

Bob and John head to Northern Spain, where a declassified document shows Hitler could have moved there from Denmark. They discover several eye witnesses, a satellite of the Third Reich, and what could be a Nazi communications center.

A mysterious email leads to what could be a huge underwater UFO base off the California coast. An investigation of new activity at Area 51 takes a dangerous turn. Plus, could an alien satellite be orbiting the Earth right now?

In Hamiltons possession is a wooden chest stuffed full of relics from medieval Christian pilgrimages. These include clamshell pendants from the Camino De Santiago in Spain and Jerusalem crosses from the Holy Land.

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.

In this episode we reconstruct the grand hypostyle hall at Karnak; explore the technical innovation and engineering skill that produced the temple at Abu Simbel and rebuild the Ramesseum as he would have seen it.

An ancient civilisation revered by scientists for their extremely accurate calendars, the Maya are also known for their mysterious ability to predict unsettling events.

A revolution in engineering is making today's technology as outdated as the horse and buggy. On this episode: Lightning LS-218, the world's fastest production motorcycle; and Hyperloop, a train faster than the speed of sound.

From the ancient napalm, Greek Fire, to the weapon that helped the Mongols create the largest ancient empire, the composite bow, which deadly weapon will claim the spot of most game-changing?

What if, for the first time in 4.5 billion years, Earth was pulled out of its orbit, sending it on a collision course into the Sun? Earth's 65-day deadly fall brings massive hurricanes, sandstorms and a heat wave that kills every last person.

The team attempts to prove if a tunnel exists behind a unique formation of rocks they believe is a secret backdoor entrance into the mountain. Battling a typhoon and possible Nazi concrete, the team ultimately finds proof of a void 40 feet below.

The team turn their attention to the Templars' moment of reckoning: the fall of the order in 1307. Coded Templar symbols lead them to a mysterious monastery in Spain that may hold clues to the knights' ultimate survival as a secret organisation.

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.

In this episode we reconstruct the grand hypostyle hall at Karnak; explore the technical innovation and engineering skill that produced the temple at Abu Simbel and rebuild the Ramesseum as he would have seen it.

An ancient civilisation revered by scientists for their extremely accurate calendars, the Maya are also known for their mysterious ability to predict unsettling events.

A revolution in engineering is making today's technology as outdated as the horse and buggy. On this episode: Lightning LS-218, the world's fastest production motorcycle; and Hyperloop, a train faster than the speed of sound.

From the ancient napalm, Greek Fire, to the weapon that helped the Mongols create the largest ancient empire, the composite bow, which deadly weapon will claim the spot of most game-changing?

What if, for the first time in 4.5 billion years, Earth was pulled out of its orbit, sending it on a collision course into the Sun? Earth's 65-day deadly fall brings massive hurricanes, sandstorms and a heat wave that kills every last person.

The team attempts to prove if a tunnel exists behind a unique formation of rocks they believe is a secret backdoor entrance into the mountain. Battling a typhoon and possible Nazi concrete, the team ultimately finds proof of a void 40 feet below.

The team turn their attention to the Templars' moment of reckoning: the fall of the order in 1307. Coded Templar symbols lead them to a mysterious monastery in Spain that may hold clues to the knights' ultimate survival as a secret organisation.

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.