Ancient Aliens

Season 21

8 episodes 22 seasons

Release Date

Premiered

Ancient Aliens Season 21 released on February 7, 2025.

Your Progress

Track your watching progress by signing in

Sign In to Track Progress

Episodes

Watched?

S21E01 Aired February 07, 2025

The Top Ten Extraordinary Discoveries

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?

S21E02 Aired February 14, 2025

The Top Ten Mysterious Monoliths

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?

S21E03 Aired February 21, 2025

The Top Ten UFO Crashes

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?

S21E04 Aired February 28, 2025

The Top Ten Unexplained Technologies

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?

S21E05 Aired March 07, 2025

The Top Ten Secret Projects

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?

S21E06 Aired March 14, 2025

The Top Ten Mysterious Mountains

"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 and a volcano in Washington that was at the center of a UFO sighting.

S21E07 Aired March 21, 2025

Mysteries of the Aztecs

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?

S21E08 Aired March 28, 2025

The Glowing Orb Phenomenon

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?