Ancient Aliens, Alien Tech

Series examining 75 million years of alien evidence on Earth. Discover what secrets extraterrestrials may have left behind and how spacemen might have shaped our world.

Why do many cultures tell similar tales of monsters and giants? Could they be eye-witness accounts of extraterrestrials? Series exploring evidence of aliens.

From Mexico's mystifying Zone of Silence, to Markawasi Plateau in Peru, known for its frequent UFO sightings, were these the homes of ancient aliens?

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.

Investigation into whether advanced technologies such as lasers and sonic weapons are merely rediscovered tools used by advanced beings in the past.

From a cave in Ecuador said to hold tablets containing alien knowledge, to an underground city in Turkey, explore supposed extraterrestrial lairs.

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

Could aliens have helped humans build huge ancient structures? Experts ask whether standing stones in France, were a GPS system for ancient spacecraft.