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Ancient Aliens Season 21 Episodes
Season 21 Episode Guide
17 Episodes 2025 - 2025
Episode 1
The Top Ten Extraordinary Discoveries
Fri, Feb 7, 202541 mins
Ancient Aliens is counting down ten of history's most astonishing discoveries-breakthroughs that challenge traditional beliefs about human history. From a lost city hidden in the Andes to mysterious metal spheres that are not of this world and a sunken city that was said to be the home of the gods, could these discoveries provide proof of extraterrestrial contact?
Episode 1
Skulls of the Gods
Thu, Jan 15, 202642 mins
In every corner of the world, archaeologists have found strange, elongated skulls. Did our ancestors modify the shape of their skulls to resemble extraterrestrials? And might it even be possible that some of these skulls are of otherworldly origin?
Episode 2
The Top Ten Mysterious Monoliths
Fri, Feb 14, 202542 mins
Ancient Aliens is counting down the world's top ten most mysterious monoliths, from a 500-ton stone believed to represent an ancient UFO, to giant statues said to have been created with advanced technology, and ornate pillars that depict otherworldly visitors. Could these extraordinary standing stones provide evidence of extraterrestrial visitation?
Episode 3
The Top Ten UFO Crashes
Fri, Feb 21, 202542 mins
Ancient Aliens is counting down ten of the most compelling UFO crashes that have been reported across the globe. From an acorn-shaped object that crashed in the woods of rural Pennsylvania, to a mysterious craft that washed ashore in Japan, and an earth-shaking impact in Britain that defies explanation, are these mysterious events proof that our planet has been visited by extraterrestrials?
Episode 3
Islands of the Gods
Thu, Nov 20, 202542 mins
In the western Pacific Ocean is a vast area known as Oceania that is home to the world's most remote and mysterious islands. They are known for massive stone structures, statuary strange figures, and countless legends of otherworldly visitors.
Episode 4
The Top Ten Unexplained Technologies
Fri, Feb 28, 202542 mins
Ancient Aliens is counting down ten of the most astonishing - and unexplainable - technologies in history. From mysterious golden orbs discovered in Mexico, to a sacred wooden box that could communicate with the heavens, and an ancient tomb that is said to depict an astronaut, might these sensational artifacts be evidence of otherworldly contact?
Episode 5
The Top Ten Secret Projects
Fri, Mar 7, 202541 mins
Ancient Aliens is counting down ten of history's most compelling - and covert - projects that study the UFO phenomenon. From clandestine government organizations to agents that silence UFO witnesses and secret programs to reverse engineer alien technology, are these mysterious projects evidence of contact with extraterrestrials?
Episode 6
The Top Ten Mysterious Mountains
Fri, Mar 14, 202542 mins
Ancient Aliens is counting down ten mysterious mountains that are notorious for otherworldly phenomena. From a summit in Sri Lanka that is said to be a portal to other worlds, a volcano in Washington that was at the center of a famous UFO sighting, and a mesa in New Mexico believed to contain an alien base, could these strange peaks provide evidence of extraterrestrial contact?
Episode 7
Mysteries of the Aztecs
Fri, Mar 21, 202542 mins
The Aztecs built one of the world's most powerful and feared empires, and they claimed that they were guided by a pantheon of more than a thousand gods who came to Earth from different parts of the universe. Could the incredible story of their rise to power-and their sudden demise-reveal a history of extraterrestrial intervention in Mesoamerica?
Episode 8
The Glowing Orb Phenomenon
Fri, Mar 28, 202542 mins
Across the globe, reports of mysterious glowing orbs are on the rise. Their movements frequently defy the laws of physics, and now they are even being reported near military bases, ships, and nuclear weapon facilities. Do they represent a non-human intelligence? And if so, why are they here?
Episode 9
The Legacy of J. Allen Hynek
Fri, Aug 29, 202542 mins
Dr. J. Allen Hynek is best known as the notorious government UFO debunker who became one of the founding fathers of ufology. Was Dr. Hynek right when he ultimately concluded that there is a non-human intelligence on Earth?
Episode 10
The Volcano Factor
Fri, Sep 5, 202542 mins
Volcanoes are Mother Nature's most fearsome and volatile creation. They have inspired countless myths and legends, but curiously, they are also major hotspots for UFO sightings.
Episode 11
The Birdman Mystery
Fri, Sep 12, 202542 mins
Throughout the ancient world, there are depictions of mysterious figures that appear to be half human and half bird. In many cultures, they are revered as divine and have magical abilities.
Episode 12
The Abduction Files
Fri, Sep 19, 202542 mins
All over the world, there are people who claim they have been abducted by aliens. Since the 1970s, a growing number of researchers have dedicated their lives to uncovering what is behind this disturbing phenomenon.
Episode 13
The Giants
Thu, Oct 2, 202542 mins
Examining how thousands of years ago, people all over the world described encounters with enormous, human-like beings; exploring how some archaeologists claim to have found skeletons of extraordinary size; is it possible the giants actually existed?
Episode 14
Aliens in Our Midst
Thu, Oct 9, 202542 mins
In the age of smartphones and social media, more evidence of otherworldly activity has come to light than ever before. From a giant "shadow monster" witnessed outside a Miami mall to reports of ET encounters in Las Vegas.
Episode 15
Britain's UFO Files
Thu, Oct 16, 202542 mins
From ancient sites like Stonehenge to the crop circle phenomenon and modern-day UFO sightings, Great Britain is a place of countless mysteries. Could it be that throughout history, this island has been a destination for extraterrestrial visitors?
Episode 16
Mysteries of the Norse Gods
Thu, Oct 23, 202542 mins
The ancient legends of the Norse read like modern science-fiction, with powerful gods wielding incredible weapons and high technology. Could it be that these mythological tales are based on real encounters with extraterrestrial beings?
Episode 17
Secrets of Japan
Thu, Nov 6, 202542 mins
Japan is a land rich with ancient mysteries, and recently, it has also become known as a UFO hotspot. Could it be, as Ancient Astronaut Theorists suggest, that this island nation has a long history of extraterrestrial activity?