The BEST episodes of Ancient Aliens season 21
Every episode of Ancient Aliens season 21, ranked from best to worst by thousands of votes from fans of the show. The best episodes of Ancient Aliens season 21!
Explores the controversial theory that extraterrestrials have visited Earth for millions of years. From the age of the dinosaurs to ancient Egypt, from early cave drawings to continued mass sightings in the US, each episode gives historic depth to the questions, speculations, provocative controversies, first-hand accounts and grounded theories surrounding this age old debate. Did intelligent beings from outer space visit Earth thousands of years ago?
#1 - Aliens In Our Midst
Season 21 - Episode 14 - Aired 10/9/2025
In the age of smartphones and social media, more evidence of otherworldly activity has come to light than ever before.
Watch Now:Amazon
#2 - The Volcano Factor
Season 21 - Episode 10 - Aired 9/5/2025
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. Is it possible that these incredible geological formations - which can generate far greater energy than the most powerful nuclear warhead - are attracting otherworldly visitors?
Watch Now:Amazon
#3 - Mysteries Of The Norse Gods
Season 21 - Episode 16 - Aired 10/23/2025
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 who continue to visit our planet even now?
Watch Now:Amazon
#4 - The Giants
Season 21 - Episode 13 - Aired 10/2/2025
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?
Watch Now:Amazon
#5 - The Birdman Mystery
Season 21 - Episode 11 - Aired 9/12/2025
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. But could these so-called 'Birdmen' have truly existed? And if so, just what were they?
Watch Now:Amazon
#6 - The Legacy of J. Allen Hynek
Season 21 - Episode 9 - Aired 8/29/2025
Dr. J. Allen Hynek was a pioneering scientist who developed smart weapons, optical tracking systems, and space satellites. Yet, he 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?
Watch Now:Amazon
#7 - Britain’s UFO Files
Season 21 - Episode 15 - Aired 10/16/2025
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?
#8 - The Abduction Files
Season 21 - Episode 12 - Aired 9/19/2025
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. Are humans really being taken off Earth by extraterrestrial entities? And if so, what is their agenda?
#9 - Mysteries of the Aztecs
Season 21 - Episode 7 - Aired 3/21/2025
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?
#10 - The Glowing Orb Phenomenon
Season 21 - Episode 8 - Aired 3/28/2025
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?
#11 - The Top Ten UFO Crashes
Season 21 - Episode 3 - Aired 2/21/2025
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?
#12 - The Top Ten Mysterious Mountains
Season 21 - Episode 6 - Aired 3/14/2025
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?
#13 - The Top Ten Extraordinary Discoveries
Season 21 - Episode 1 - Aired 2/7/2025
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?
#14 - The Top Ten Secret Projects
Season 21 - Episode 5 - Aired 3/7/2025
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?
#15 - The Top Ten Mysterious Monoliths
Season 21 - Episode 2 - Aired 2/14/2025
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?
#16 - The Top Ten Unexplained Technologies
Season 21 - Episode 4 - Aired 2/28/2025
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?