Throughout history, powerful nations around the world have enlisted spies to serve as unique tools of warfare. These secret agents are often tasked with infiltrating organizations and even performing the act of assassination.

For thousands of years, people have believed in the existence of Satan, the embodiment of evil. Some believe he has the power to possess souls and create mayhem amongst humanity. But is Satan a myth? Or are there signs of Satan's existence--and the evil he brings into our world?

Ancient practices such as prayer, blood sports, voodoo, and exorcism are often thought to be relics of bygone superstition – but there is evidence they have an impact on the physical world. Is it possible that the mind and body can use the power of ritual to tap into hidden forces that lie just beyond the grasp of conventional explanation?

Throughout human history, diverse cultures have all used sacred rituals to express their spiritual beliefs. And while some ceremonial practices may appear strange, there are many rituals that are thought to unlock incredible powers. So, is it possible that performing certain acts can connect humanity to a higher plane of existence?

Mankind has always pondered what happens after death and what we leave behind. Many wonder, what power our bones may hold. Some believe, bones can bring good luck or even allow us to speak with the dead. But is it possible that our bones hold some sacred power, or perhaps even our souls?

Dracula. Lycaon of Arcadia. The Beast of G vaudan. These are the names of grotesque monsters who have reared their terrifying heads throughout history. Unearthly creatures that, according to legend, thrived on human blood - and feasted on flesh. Vampires and Werewolves are human monsters, creatures of the night. But, could they actually be... real'

For centuries, legends and eyewitness accounts have told of a massive, hairy creature that roams the forest on two legs. While science has yet to prove the existence of this mythical man-beast, countless researchers and experiencers around the world are convinced that there is a giant, ape-like animal hiding in remote parts of the world. They point to the discovery of large, inexplicable footprints as evidence of the so-called "Bigfoot" that they hope to prove is real. But does Bigfoot actually exist?

Many see them as massive testaments to America's progress. Some view them as immutable symbols of the human spirit. Others perceive them as sacred shrines dedicated to the ideals of liberty and freedom. But no matter what they represent--America's monuments are inarguably impressive due to their colossal size and scope, their groundbreaking feats of engineering, and their storied histories. Why is it that America's greatest monuments continue to enthrall us decades--and sometimes centuries--after their creation? And perhaps more importantly, what closely guarded secrets may their implacable facades be hiding?

A meteorite falling from the heavens. A gemstone with a deadly curse. A sandstone so sacred that wars have been fought to protect it. Stones that can choose a king or cause death. What's it about stones that inspire people to worship them?

From ancient civilizations to 20th century empires, mankind has had an inexplicable fascination with preserving the dead. But why? Are we simply too attached to the living to let them go? Or could it be that death isn't really the end, but rather a transition to a new beginning?

Gold. It's one of the most valuable precious metals on the planet, has been coveted by societies for centuries, and can be found inside countless modern electronics. Mankind's quest for gold harkens back thousands of years, but what is the special power that gold wields over our collective consciousness? Is it merely because it's rare and valuable, or could it be something more than that?

The American frontier is full of legends of cowboys, Native Americans, and outlaws. But there are also many eerie stories of cursed mountains, monsters and even UFOs. Could these tales be true? Is the Wild West much stranger than commonly though?

Throughout history, every major civilization has believed in curses, and their power to inflict harm on the unsuspecting. Today, many people are still afraid of walking into a cursed place or touching a reportedly-cursed object. But if curses are real then what brings them into existence? And how are they triggered?

Millions of people around the world claim to have had an encounter with a creature unlike any recognized by mainstream science – such as the Mothman, Chupacabra, and Mongolian Death Worm. Could these incredible creatures be real? And if so, what could possibly explain these freaks of nature?

Throughout history, many have believed that certain places, things, or even people can be tainted with dark curses. Ominous lakes that morph into watery graves. Unlucky numbers that seem to cause bad things to happen. Paintings and precious stones, which bring death and destruction to their keepers. But can these mysterious curses really have the power to bring us harm? And if so, is it possible to understand their power, or will it remain UnXplained?

The total disregard for life exhibited by serial killers shocks our sense of humanity and makes us question our safety and security. These sadistic psychopaths rarely show any remorse or empathy for the lives they've destroyed. How could human beings be capable of these horrific atrocities? And what causes such a murderous defect in the human psyche?

Throughout history, many have sought the lost Ark of the Covenant. According to the Old Testament, God himself instructed Moses to build the Ark--and it is believed that it held the power of the Almighty. But how could such a coveted religious artifact just disappear? And is it possible that the Ark could actually be found?

All over the world, there are places and objects that are thought to be cursed; many people avoid these locations and things, believing they will bring harm, while others think that curses are nothing more than superstition and folklore.

Deadly forest. Haunted houses. Mountains where visitors never return alive. Are there such things as "evil places"? Places where bad things seem to repeatedly -- and inexplicably -- happen? And if so, is it possible that these locations are imbued with dark energy that is currently beyond our understanding?

How do some people live through the impossible? Whether it's plane crashes, bearing freezing temperatures, or performing superhuman feats while in danger ? remarkable tales of human survival force us to reconsider what we know about our own will to live. Do we have a hidden reserve of inexplicable energy locked away inside us ? that only gets released when the situation calls for it?

Many believe it to be the Word of God, but others claim it contains inconsistencies and contradictions that could only be manmade.

According to the Greek philosopher Plato, the lost continent of Atlantis was once home to an advanced civilization before it was destroyed in a cataclysm. But was Plato's story merely a myth? Or did Atlantis really exist? For centuries, archaeologists have tried to uncover evidence to prove that this legend is true. Will Atlantis finally be re-discovered, perhaps by employing modern technology? Or will this lost civilization remain...UnXplained?

Will we ever understand the motivations that drive people to undertake the most bizarre, intricate, and dangerous crimes -- or will the mind of a master criminal remain - UnXplained?

Since the dawn of civilization, humanity has been fixated on predicting our own demise. Perhaps it will be asteroids, black holes, or something even more mysterious that will wipe us out. But is there anything we can do to predict the future and protect ourselves from apocalypse? Will our civilization end--or will we find a way to evolve and endure?

Genius is widely considered to be the ability to change the world in an incredible way: inventing new technology, deciphering the mysteries of the universe, or creating transcendent art. But where does genius come from? What is the X-factor that makes someone a genius? Is it "good genes"? A proper education? Or do geniuses tap into something much more mysterious and extraordinary?