Puma Punku in Bolivia features stone blocks, each carved with precision; the blocks lie scattered across the landscape, confusing archaeologists as to what the ancient site might have been.

From biblical patriarchs to modern day alien abductees, throughout history, there have been people who claimed to have contact with otherworldly beings; often bearing important messages for humanity.

For more than four decades, award-winning journalist Linda Moulton Howe has covered the most mysterious phenomena on Earth. Could her investigations on everything from bizarre animal deaths to crop formations and alien abductions lead us to a profound new reality?

Deep beneath the sands of Egypt lie 24 enormous sarcophagi, and every one of them is empty; discussing what purpose those giant tombs had served.

Stories of god-like beings providing instruction to early humans, helping establish the first civilizations; exploring if mysterious figures who appear throughout history provide evidence that these otherworldly teachers have been here all along.

Dr. Jacques Vallée has many scientific degrees, is a best-selling author and is regarded as one of the internet's founding fathers. But he is best renowned for his groundbreaking work on the subject of UFOs, where his bold theories call into question our understanding of alien life.

For thousands of years, humankind has attempted to make contact with beings from beyond Earth; now, the search for extraterrestrial intelligence is ramping up, with new technologies allowing individuals to explore the universe.

For decades, incredible claims have been made about an extraterrestrial presence on Earth, and the government has gone to great lengths to discredit them.

For thousands of years, cultures around the world have held a belief in stargates through which beings have traveled to Earth from distant points in the universe and even other dimensions. Could such portals truly exist? And if we obtain the key to unlocking the stargates, will we find a cosmos teaming with life?

Considered by many to be the greatest civilization in the history of the Americas, the Maya thrived for more than 2,000 years. Now, new evidence is being discovered that completely upends our understanding of this ancient culture... and might provide evidence that the Maya came in contact with extraterrestrial visitors.

Throughout the world there are mysterious ancient stones shaped into perfect spheres; many of them show clear evidence of being manmade and some completely defy explanation; the mystery of the stone spheres could provide clues about humankind's past.

For thousands of years, Scotland has been an epicenter of otherworldly phenomena; it is home to mysterious ancient stone circles, stories of strange beings, and is a major hotspot for UFO sightings.

Along the Earth's north 37th parallel there have been so many reports of unidentified flying objects, animal mutilations, and other mysterious events that it has been dubbed The UFO Superhighway. Could there be something about this latitude that is attracting extraterrestrial visitors?

More than 7,000 years ago, the ancient Sumerians established what is considered the world's first civilization and they credited their extraordinary achievements to their gods, the Anunnaki. But is it possible that these powerful beings were, in fact, extraterrestrial visitors to Earth?

Ancient Aliens is counting down the top ten most devastating disasters ever documented that might have an otherworldly connection, from a flying monster at a nuclear incident, a meteor that wiped out the dinosaurs, and a deadly virus that might be from another world. Could these disasters be proof of extraterrestrial contact?

Ancient Aliens is counting down ten of the most intriguing--and mysterious--symbols and codes found across the globe that just might contain proof of otherworldly contact. From glyphs in the Peruvian desert, to spiral petroglyphs embedded with advanced math, and a language with an otherworldly origin, could these codes unlock the secrets of our extraterrestrial past?

This episode promises a countdown of the most unsettling and enigmatic incidents that suggest possible visitations from beings beyond our world. From a perplexing incident in rural Texas that left witnesses with unexplainable injuries to the eerie phenomenon of mysterious cattle mutilations, each story unfolds to explore the possibility of extraterrestrial involvement. With a mix of firsthand accounts, expert analysis, and chilling reenactments, “Ancient Aliens” delves into the uncharted territories of unexplained phenomena, leaving viewers on the edge of their seats as they contemplate the mysteries that may lie beyond the stars.

Counting down the top 10 locations around the world that may be hiding alien bases, including a cavern beneath the ice of Antarctica, a lake in China that is a hotspot for UFOs, and a pyramid under the slopes of Mount Denali...

For more than a decade, Ancient Aliens has collected dozens of reports of encounters with strange and mysterious beasts. Now, Ancient Astronaut Theorist Giorgio Tsoukalos takes a look back at The Top Ten Extraordinary Creatures we've investigated--creatures that just might provide compelling evidence of extraterrestrial visitation...

Did a biblical patriarch receive instructions from 200 Angels high above the earth? Were the ancient Greeks taught how to work metal by a race of fish-people? And might Egypt's most controversial Pharoah have been an extraterrestrial being? Giorgio Tsoukalos looks at mysterious teachers who have appeared throughout history and reveals The Top Ten Alien Influencers who he believes provide the ultimate proof of extraterrestrial contact...