Ancient Aliens: The Series (2010)

A look at possible alien contact events during the 20th century, such as the Battle of Los Angeles in 1942 and the Roswell UFO Incident in 1947; the recent attempts by man to make contact with extraterrestrial life through the CETI project; and what would happen if aliens answered back, what protocols exist to determine who would speak on behalf of mankind and how we would communicate.

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