Deep beneath the sands of Egypt lie 24 enormous sarcophagi–and every one of them is empty. What purpose might these giant tombs have served? And is it possible that the perfectly carved stone boxes–each weighing more than 70 tons–were designed not by humans… but by otherworldly visitors?

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Throughout the world there are mysterious ancient stones shaped into perfect spheres. Many of them show clear evidence of being manmade and some completely defy explanation. Could the mystery of the stone spheres provide clues about humankind’s alien past?

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For thousands of years, humankind has attempted to make contact with beings from beyond Earth. Now, in the 21st century, the search for extraterrestrial intelligence is ramping up like never before, with powerful new technologies allowing us to explore billions of stars across the universe. Are we on the verge of first contact?

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Did a biblical patriarch receive instructions from 200 angels high above the earth? Were the ancient Greeks taught how to work metal by a race of fish-people? And might Egypt’s most controversial Pharoah have been an extraterrestrial being? Giorgio Tsoukalos looks at mysterious teachers who have appeared throughout history–and reveals The Top Ten Alien Influencers who he believes provide the ultimate proof of extraterrestrial contact.

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Dr. Jacques Vallee holds multiple scientific degrees, is a best-selling author, and is one of the fathers of the internet. But he is best known for his revolutionary work in the field of UFOs, and his bold theories challenge our notions of alien life. Will Dr. Vallee’s incredible work soon lead to answers about what has been happening in our skies for thousands of years?

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For thousands of years, cultures around the world have held a belief in stargates through which beings have traveled to Earth from distant points in the universe and even other dimensions. Could such portals truly exist? And if we obtain the key to unlocking the stargates, will we find a cosmos teaming with life?

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Considered by many to be the greatest civilization in the history of the Americas, the Maya thrived for more than 2,000 years. Now, new evidence is being discovered that completely upends our understanding of this ancient culture… and might provide evidence that the Maya came in contact with extraterrestrial visitors.

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For more than a decade, Ancient Aliens has collected dozens of reports of encounters with strange and mysterious beasts. Now, Ancient Astronaut Theorist Giorgio Tsoukalos takes a look back at The Top Ten Extraordinary Creatures we’ve investigated–creatures that just might provide compelling evidence of extraterrestrial visitation.

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It is one of the greatest mysteries of the prehistoric world: why did people on nearly every continent erect giant standing stones? According to Ancient Astronaut Theorists, the placement of these monoliths and their geological makeup could point to extraterrestrial intervention–and, quite possibly, a technology that once existed on Earth far more advanced than our own.

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For thousands of years, Scotland has been an epicenter of otherworldly phenomena. It is home to mysterious ancient stone circles, stories of strange beings, and is a major hotspot for UFO sightings. Could it be that Scotland is a magnet for extraterrestrial visitors?

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