Episode Guide

The Lost City of Peru

Ancient Astronaut theorists Giorgio Tsoukalos, David Childress, and William Henry converge on Peru to investigate whether recent discoveries at sites like Caral suggest extraterrestrial involvement in South American civilization. The episode challenges the conventional timeline that credits the Inca Empire (13th-16th century AD) with Peru's megalithic achievements at Cusco, Sacsayhuamán, Ollantaytambo, and Machu Picchu. The theorists argue that the dating of Caral—a pre-ceramic settlement on Peru's coast—has upended the accepted chronology, revealing advanced construction thousands of years before the Inca. They propose that structures featuring massive stone walls and precise engineering required help from beings from another world, pointing to local legends of giants and "children of the sun" as encoded memories of extraterrestrial contact.

Top Ten Mysterious Sites

Giorgio Tsoukalos and the Ancient Aliens team count down their top ten most mysterious ancient sites, arguing that locations like the Nazca Lines in Peru and Easter Island's moai statues provide compelling evidence of extraterrestrial visitation. The Nazca Lines—massive geoglyphs depicting animals, geometric shapes, and lines carved into the desert floor between the first and eighth centuries AD—can only be fully appreciated from the air, which Erich von Däniken interprets as signals created by ancient peoples to communicate with "beings up there." Similarly, Easter Island's nearly 1,000 enormous stone moai, some transported over 11 miles from their volcanic quarry, present what the show frames as engineering puzzles that challenge conventional explanations of what ancient cultures could achieve without modern technology.

Top Ten Alien Cover-Ups

This countdown episode revisits what host Giorgio Tsoukalos considers the most compelling government cover-ups regarding UFOs, beginning with the December 2017 New York Times revelation of AATIP—the Pentagon's Advanced Aerospace Threat Identification Program. Former Pentagon intelligence officer Luis Elizondo ran the program from 2007 to 2012, investigating unidentified aerial phenomena captured by military personnel. After resigning in 2017 to protest what he characterized as excessive secrecy, Elizondo helped release three Navy jet videos showing objects maneuvering in ways that seemingly defied conventional aerodynamics. Ancient astronaut theorists, including Nick Pope who argues this represents "the single biggest ever news in the whole history of the UFO phenomenon," interpret these official acknowledgments as confirmation that governments possess evidence of extraterrestrial visitation. The episode also covers Area 51, whose existence the CIA finally acknowledged in 2013 after decades of denial.

Top Ten Places Aliens May Have Visited

Ancient astronaut theorists Giorgio Tsoukalos, David Childress, and William Henry investigate Mount Shasta in northern California—a 14,179-foot dormant volcano they argue may serve as a nexus for extraterrestrial and interdimensional contact. The team points to centuries of documented anomalies: UFO sightings above the peak, reports of beings vanishing into cave walls, and Native American warnings about forbidden zones above the tree line. Local guide Jack "Walking Eagle" Thom describes firsthand encounters with unexplained phenomena, while Nick Pope notes the mountain's history of strange disappearances stretching back through indigenous oral traditions. The theorists suggest Mount Shasta's unique geology and geographic placement may attract otherworldly visitors, with Childress speculating it could be where extraterrestrials "finally reveal themselves."

The Mystery of Skinwalker Ranch

Ancient astronaut theorists Giorgio Tsoukalos and David Childress convene a panel discussion exploring whether human DNA itself contains evidence of extraterrestrial intervention. The episode centers on a puzzling gap in evolutionary theory: if natural selection alone drove human development, why did only Homo sapiens survive among seven contemporaneous human-like species, and why did we alone develop technology-building intelligence that no other primate or intelligent animal has matched? The theorists point to Genesis 1:26's plural phrasing—"Let us make man in our own image"—as potential evidence that "gods" (interpreted as extraterrestrials) genetically engineered early humans. Filmmaker Caroline Cory and Rabbi Ariel bar Tzadok join the discussion, suggesting DNA's programmable, information-storing nature indicates intelligent design rather than random mutation.

The Mystery of Mount Shasta

Ancient Aliens host Giorgio Tsoukalos counts down his top ten most compelling extraterrestrial encounters, starting with the Hudson Valley UFO sightings of 1982-1988. On New Year's Eve 1982 near Kent, New York, hundreds of witnesses reported seeing a massive V-shaped craft with pulsating lights hovering over the Hudson River area—sightings that continued for six years and generated an estimated 5,000 reports. Ancient astronaut theorists including Tsoukalos suggest these concentrated sightings occurred because the Hudson Valley sits atop an Earth energy "vortex," similar to supposed vortex sites at Stonehenge and Sedona, Arizona, which may create portals through time and space that attract extraterrestrial visitors. The episode also examines the 1961 Betty and Barney Hill case in New Hampshire, described as the first documented alien abduction report in history.

The Human Experiment

In this retrospective countdown episode, Giorgio Tsoukalos ranks his top ten "alien artifacts" that he believes suggest extraterrestrial visitation in antiquity. The list includes the Mitchell-Hedges crystal skull, discovered in 1924 at Lubaantun, Belize, which Tsoukalos claims was analyzed by Hewlett-Packard and found to be carved against the crystal's natural axis—something that should cause quartz to shatter without modern power tools. Ancient astronaut theorists point to legends across cultures describing exactly thirteen crystal skulls of otherworldly origin scattered globally, and suggest these objects may store advanced information in the crystal matrix, just as modern technology uses quartz for data storage. The episode also features the Saqqara Bird from Egypt, a wooden object theorists describe as resembling a modern glider rather than a simple bird figurine.

Top Ten Alien Encounters

Countdown of the top ten alien encounters.

Top Ten Alien Artifacts

Examines the top ten alien artifacts.

Top Ten Mysterious Creatures

Countdown of the top ten mysterious creatures with alien connections.