These special compilation episodes of "Ancient Aliens" explore the controversial theory that extraterrestrials have visited Earth for millions of years.

Examining whether shadow people, spirits, poltergeists and other strange beings that have appeared in ancient texts and folklore could be otherworldly visitors that originate from unseen realms and ...

Ancient Astronaut theorists have long proposed that Earth is an extraterrestrial laboratory. If so, does it extend beyond humans into the animal kingdom? Accounts of animalist gods can be found across ...