Giorgio Tsoukalos takes a look back at the most compelling investigations of all, and events that he believes represent real encounters with extraterrestrial visitors.

Human can survive catastrophic injuries and deadly scenarios that defy the odds in ways that are inexplicable. Is cheating death when survival is seemingly impossible simply fate or good fortune?

After conducting an experiment that reveals more evidence in the skies above Skinwalker Ranch, the team turn their attention to under the ground.

In California, Ton and Allen uncover a vicious high speed Quadzilla ATV and a pair of assassin's guns - a 1910s Remington Derringer and an 1880s Palm Squeezer. (Series 2,

The guys score a turn-of-the-century Thomas Edison gramophone with rare wax cylindrical records, and a one-man Addictor 190 Mini Boat designed for high-speed fun. (Series 2,

Human can survive catastrophic injuries and deadly scenarios that defy the odds in ways that are inexplicable. Is cheating death when survival is seemingly impossible simply fate or good fortune?

From glyphs in the Peruvian desert to spiral petroglyphs embedded with advanced maths, explore some of the world's most intriguing symbols and codes.

Four smiths face a challenge to salvage steel from five tons of junk, while two more smiths forge the longest weapon in the show's history.

The Harrisons own and run Gold & Silver Pawn in Las Vegas, Nevada. Who would have thought that this ordinary, at first glance, family business would be such a high maintenance.

In California, Ton and Allen uncover a vicious high speed Quadzilla ATV and a pair of assassin's guns - a 1910s Remington Derringer and an 1880s Palm Squeezer. (Series 2,

The guys score a turn-of-the-century Thomas Edison gramophone with rare wax cylindrical records, and a one-man Addictor 190 Mini Boat designed for high-speed fun. (Series 2,

The Pawn Stars check out more curios, knick-knacks and memorabilia as the ever-popular series returns for a 23rd season.

Four bladesmiths are tasked with forging a Saw Back machete and later create a deadly Malaysian backcountry tool and weapon: the infamous, Parang Nabur.

Ton and Allen jet to the Hawaiian islands where they're joined by a new assistant. The team uncover a pair of James Bond-style gadgets and a vintage sledge.

Titanic Pawn: A 1906 Silver Half Dollar that belonged to a passenger on the Titanic sails into the shop. Will Rick snap it up or will it sink without trace?

A set of playing cards from 1769 with a hidden political message shuffles into the shop, while Corey checks out a set of Charlie's Angels figurines.

In this head-to-head final round, bladesmiths must recreate Butterfly Swords - deadly combat swords that are ideal for chopping.

Four smiths have to create a knife from the most mangled mess of a vehicle ever seen on the forge floor. Only one smith can prevail. Season premiere.

Storage-unit auctions are the newest and biggest untapped source for hidden treasures, and opportunistic individuals bid on unclaimed properties hoping to strike gold. Welcome to Storage Wars.

Orange You Glad Dan Sold It Again?: The bidders head to auctions in Burbank, where a new buyer challenges both Barry and Jarrod, before making off with a jam-packed locker.

The team goes on the attack and ends up on a collision course with a veteran auction buyer. They uncover a collection of speedy off-road vehicles and some hardcore heavy metal.

The Auction Hunters team goes toe-to-toe with Ton's evil twin! They find a medieval catapult designed for storming castles and Ton uncovers gold bars worth thousands of dollars.

Chum chases a lead on a 1963 Fiat Microcar. Meanwhile, Rick and Corey make a wager on a set of billiard balls and Rick examines the holy grail of coins.

From glyphs in the Peruvian desert to spiral petroglyphs embedded with advanced maths, explore some of the world's most intriguing symbols and codes.

Ancient Astronaut theorists have long proposed that Earth is an extraterrestrial laboratory. If so, does it extend beyond humans into the animal kingdom? Accounts of animalist gods can be found across the globe that curiously mirror alien encounters.

Eerie encounters at 40,000 feet, accounts of UFOs taking control of aircraft, and jumbo jets disappearing. Is this proof of aliens in our airspace?

A piece of the 1990s rolls into the shop as the guys check out ""The Mirthmobile"" from 'Wayne's World'. Can they resist a blast of Bohemian Rhapsody while taking it for a test ride?

For millennia, people have believed that everyday objects can possess hidden energy. These talismans are seen to provide protection and good fortune.

Dr. Travis Taylor relives the most shocking and compelling phenomena that have taken place in the past year on Skinwalker Ranch.

The Harrisons own and run Gold & Silver Pawn in Las Vegas, Nevada. Who would have thought that this ordinary, at first glance, family business would be such a high maintenance.

Human can survive catastrophic injuries and deadly scenarios that defy the odds in ways that are inexplicable. Is cheating death when survival is seemingly impossible simply fate or good fortune?

After conducting an experiment that reveals more evidence in the skies above Skinwalker Ranch, the team turn their attention to under the ground.

An abandoned concrete wall. Five strange deserted structures. A lost escape route from nuclear Armageddon. A submerged link to D-day. Who built them? And why were they abandoned?

Four bladesmiths are tasked with forging a Saw Back machete and later create a deadly Malaysian backcountry tool and weapon: the infamous, Parang Nabur.

More than 10,000 crop circle formations have been documented and many display properties that defy explanation. Could they be of otherworldly origin?

During World War II, the Nazi war machine creates specialised death camps. At Sobibor, Poland, a small number of Jews engineer a mass escape.

A trio risk it all to steal priceless jewels at the American Museum of Natural History, creeping 125 feet above the streets of Manhattan.

England's first pop culture superhero, King Arthur's exploits have inspired numerous blockbuster movies and television series. A testament to the power of myth? Or the enduring legacy of fact?

An abandoned concrete wall. Five strange deserted structures. A lost escape route from nuclear Armageddon. A submerged link to D-day. Who built them? And why were they abandoned?

Forty miles west of La Paz, Bolivia - high in the Andes Mountains - lie the mysterious ancient ruins of Puma Punku. Could it have been built by extraterrestrials?