Henry Carter Hull

Serpent gods are found in the religious traditions of Mesopotamia, Central and South America, India, China and Japan. Even the Bible describes reptilian entities interacting with humans.

Unearthly visitations... Heavenly messengers... Close encounters... Accounts of humans interacting with celestial beings have existed since the beginning of mankind.

Ancient underwater cities can be found around the globe, but could these aquatic worlds be the ruins of unknown civilizations--or even proof of extraterrestrial visitations?

Ancient Astronaut theorists believe aliens have been visiting earth for thousands of years. If so, might we find evidence of this even in the stories of America's Old West?

Why are humans so different from every other species on Earth? Did we evolve from ape--or is our intelligence the result of contact with an otherworldly source? Could unexplained advances in human evolution be the work of interstellar beings?

There is evidence that suggests we experienced 20th century alien contact. In 1942, the Battle of Los Angeles involved the US military and Air Defense allegedly fighting a UFO.

Mysterious legends and crumbling ruins are all that is left of our planet's lost worlds. But could there be proof of ancient alien visitors hidden among the artifacts of civilizations that have long vanished?

Giorgio Tsoukalos takes a look back at the most mysterious artifacts from all over the globe - artifacts that he believes provide undeniable proof of extraterrestrial contact.

What is the meaning behind secret messages found throughout Washington, D.C.? Did America's Founding Fathers know something about ancient aliens that the general public did not? And if so, could this knowledge have been incorporated into the symbols?

Giorgio Tsoukalos takes a look back at the most extraordinary encounters that, as far as he's concerned, provide evidence of an extraterrestrial presence on Earth.