Series examining 75 million years of the most credible 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 eyewitness accounts of extraterrestrials? This series examines evidence of aliens on Earth.
From Mexico's mystifying Zone of Silence to Markawasi Plateau in Peru, known for its frequent UFO sightings, were these the homes of ancient extraterrestrials?
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.
During World War II, rumours spread that an aircraft had been built from extraterrestrial blueprints. Were aliens helping Hitler's quest for world domination?
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 metal tablets containing alien knowledge, to an underground city in Turkey, these are the stories of 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 Carnac, France, were a GPS system for ancient spacecraft.
Ruins in Peru support legends of a sunken UFO base, and Indian texts talk of water worlds populated by humans and aliens. Could aquatic cities prove that aliens visited?