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.

Texts, archaeology and legend contain evidence of past human-extraterrestrial contact.

Texts, archaeology and legend contain evidence of past human-extraterrestrial contact.

Planes and ships go missing in the Bermuda Triangle; magnetic anomalies in Mexico's Zone of Silence; an ancient doorway carved in Peru's Puerta de Hayu Marka; Markawasi's plateau' strange rock formations.