From alleged alien bases to perplexing anomalies, join us as we probe the secrets hidden within the moon's shadowy landscape in this Ancient Aliens compilation. Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The HISTORY Channel ...

Could there be a connection among the numerous pyramids found scattered around the world? And if so, did these monuments once serve an extraterrestrial purpose, as Ancient Astronaut theorists suggest? Find out in this clip from Season 2, Episode 11, "EXTRATERRESTRIAL PYRAMIDS." Watch all new ...

After 12 years of excavations, archaeologists make a shocking discovery. See more in this scene from Season 2, Episode 11, "Extraterrestrial Pyramids." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

Could the pyramids around the globe be somehow interconnected? See more in this scene from Season 2, Episode 11, "Extraterrestrial Pyramids." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

Is it possible that shadow people, spirits, poltergeists, and other enigmatic entities are rooted in reality? See more in this scene from Season 2, Episode 12, "Aliens and the Unseen." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows ...

Governments are openly investigating UFO and extraterrestrial sightings. See more in this compilation from Ancient Aliens. Watch your favorite episodes of Ancient Aliens on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for more from Ancient Aliens and ...

These strange beings have appeared in ancient texts and folklore worldwide, hinting at a more profound significance to this phenomenon. Learn more in this scene from Ancient Aliens Season 2, Episode 12, "ALIENS AND THE UNSEEN." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and ...

Billions of dollars have been spent in our quest to find an "other Earth." See more in Season 10, Episode 6, "The Other Earth." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The HISTORY Channel website at ...

According to ancient Mesopotamia texts, the Epic of Gilgamesh tells the tale of a giant creature of extraterrestrial origins, in this clip from Season 4, "Aliens and Bigfoot." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The ...

Is it possible that shadow people, spirits, poltergeists, and other enigmatic entities are rooted in reality? See more in this scene from Season 2, Episode 12, "Aliens and the Unseen." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows ...

In August of 2014, Russian cosmonauts aboard the International Space Station discovered something incredibly unexpected covering parts of the windows--living sea plankton. See more in Season 10, Episode 7, "Creatures of the Deep." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and ...

Could it really be that these otherworldly visitors coexist among us, crossing over from unseen dimensions into our world? Find out in this video from Season 2, Episode 12, "ALIENS AND THE UNSEEN." Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your ...