Season Four of the History Channel's popular television show Ancient Aliens continues the search for evidence of extraterrestrial interaction with humans. Includes interviews with David Hatcher Childress, Giorgio Tsoukalos, Erich von Daniken, Christopher O'Brien and many others. Includes all ten revealing episodes: The Mayan Conspiracy; The Doomsday Prophecies; The Greys; Aliens and Mega-Disasters; The NASA Connection; The Mystery of Puma Punku; Aliens and Bigfoot, The Da Vinci Conspiracy; The Time Travelers; Aliens and Dinosaurs. 

ANCIENT ALIENS SEASON 4 Blue-Ray DVD. 360 Minutes. 2 DVDs in Box.