Searching for clues about whether aliens visited ancient Earth in Indian Sanskrit texts, megalithic stone structures in Egypt and Jewish Zohar writings.

Investigating possible historic evidence and beliefs around the globe in search of signs that aliens visited ancient Earth; Hopi and Zuni Indians celebrate Kachina sky gods; the Chinese legend of Huangdi arriving on Earth on a flying dragon.

Strange evidence in cultures throughout history indicates aliens came to Earth on missions to explore, obtain raw materials, experiment on humans and conquer; Sumerian tablets describe an alien race; Egyptian hieroglyphs depict hybrid creatures.

Reports of encounters with strange beings and sightings of mysterious objects in the sky have occurred throughout history. A 13th century historical book, Otia Imperialia, includes an account of a creature descending from a flying craft over Bristol, England. The log from Christopher Columbus' first voyage to America contains a report of strange lights in the sky. Medieval art pieces depict disc-shaped objects floating in the heavens. Sightings of flying cigar-shaped crafts were reported during the Black Plague. And there were even discussions of extraterrestrial life among America's Founding Fathers. Could these sightings, coming from every part of the world, from biblical times to present day, be evidence that aliens have been with us all along?

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. WWII Allied Air Force planes were buzzed by balls of light that some think could have been extraterrestrial. And the alleged crash of a flying saucer in Roswell, New Mexico in 1947 propelled the world into the age of UFOs. For decades, some people have been searching for the sounds of extraterrestrial intelligence, while others have been sending messages out into deep space. What would happen if aliens answered... or came calling? What protocols exist to determine who would speak on behalf of mankind, and how might we communicate? What happens if they return? Some believe they already have.