Lurking in the oceans are creatures that defy explanation, such as octopuses that can edit their own DNA or animals that can regenerate their entire brain; examining if the oceans are acting as a giant petri dish for alien genetic experimentation.

The episode was rated 7.50 from 205 votes.

In 2016, scientists made the astonishing discovery that 30 percent of all protein adaptations since humans' divergence with chimpanzees have been driven by viruses. Could ancient aliens have shaped human evolution by introducing viral epidemics on Earth? And if so, for what purpose? Are they making us more like them?

The episode was rated 7.51 from 194 votes.

A shocking study reveals that the original builders of Stonehenge mysteriously vanished; but Stonehenge's mysterious Bluestone circle could have activated a portal that transported the ancient culture back to their former home among the stars.

The episode was rated 7.53 from 142 votes.

When Spanish Conquistadors obliterated the historical record of the Maya in the 16th century, did they wipe out evidence that ancient people traveled to the Americas from all over the world – and in flying craft provided by extraterrestrial visitors?

The episode was rated 7.53 from 210 votes.

A mysterious mountain in northern Italy has stood witness to strange sightings in the sky and unexplainable phenomena for hundreds of years but could it be attracting extraterrestrial visitors and there could be technology within its rocky slopes.

The episode was rated 7.55 from 169 votes.

Satellite images have revealed a giant face that appears to be carved into the Earth in Alberta, Canada, which has now become known far and wide as "The Badlands Guardian."

The episode was rated 7.56 from 250 votes.

Aliens from the tiny star Sirius B may have visited humans in the distant past, imparting the knowledge of civilization to peoples thousands of miles apart.

The episode was rated 7.63 from 240 votes.

Are governments around the world preparing mankind for the most startling event in human history-the official disclosure of an extraterrestrial presence on Earth? And if so, why is this happening now and what might happen in its aftermath?

The episode was rated 7.63 from 145 votes.

Tattoos, piercings, and body modification account for a nearly one-billion-dollar industry, but are these practices a bold form of self-expression or could they be motivated by a profound link to ancient ancestors.

The episode was rated 7.63 from 124 votes.

Antarctica may serve as home base for extraterrestrial visitors to Earth, but as human exploration of the frozen continent increases, humans may come face to face with the ruins of an ancient advanced civilization buried beneath the ice.

The episode was rated 7.63 from 348 votes.

Ever since the first atomic bomb was detonated in 1945, UFOs have been reported at nuclear facilities all over the world. Is it possible that extraterrestrials are monitoring humanity's nuclear capabilities? But why? Does this constitute a threat? Or are they trying to ensure humankind's survival?

The episode was rated 7.64 from 173 votes.

Divine substances were consumed by the gods but sometimes gifted to humans to impart great power or wisdom; could the food of the gods be sustenance for alien visitors and does it lend insight into humanity's future.

The episode was rated 7.64 from 154 votes.

The Infamous Alien "Element 115" mentioned by Bob Lazar over a decade ago is added to periodic table nowadays.

The episode was rated 7.66 from 262 votes.

In 2019, millions responded to an internet post advocating to storm the gates of the world's most top-secret military installation -- Area 51 but when they did, the U.S. military vowed to defend the base with deadly force.

The episode was rated 7.66 from 131 votes.

Did intelligent beings from outer space visit Earth thousands of years ago? 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.

The episode was rated 7.88 from 150 votes.