In 1997, thousands of people in Phoenix witnessed strange lights; this could be an UFO sighting.

A look at what could cause mysterious vanishings in the Bermuda Triangle, a 500,000 square mile area of the Atlantic where ships, planes and unsuspecting travelers have been lost without a trace.

During World War II, Japan plunders a fortune worth hundreds of billions of dollars from occupied countries, but to this day its whereabouts are unknown.

In 1914, Sir Ernest Shackleton led an expedition to Antarctica but soon after arrival, Shackleton's ship--The Endurance--was destroyed by shifting glaciers, and he was tasked with leading his 27 men across the tundra, on an epic struggle for survival. Shackleton's battle against the odds and his unfailing commitment to bring all his men out alive turned him into a legend. The ship's final resting ground remains one of the greatest polar mysteries. Led by maritime archeologist and shipwreck expert, Mensun Bound, follow a new ground-breaking expedition heading back into the frozen seas to hunt down Shackleton's lost ship.

A cryptic journal sparks an unprecedented investigation into whether a UFO crashed at Roswell, NM in 1947. Major Jesse Marcel, the first government official on the scene, believed to his dying day that an extraterrestrial spaceship plummeted to earth and the U.S. government covered it up. Now, the Marcel family has come forward with a journal found among Marcel's possessions. The journal may contain coded-clues to the truth behind Roswell. Former CIA operative Ben Smith embarks on a new investigation that includes a cryptographic analysis of the journal, a high tech geological study of the crash site, and interviews with witnesses who have never spoken publicly. What really crashed in Roswell? The US government claimed it was a weather balloon and then changed its story. Others spoke of alien bodies, and extreme government intimidation.

A former CIA operative's investigation into the Roswell crash arrives at a critical moment when the mysterious journal found among the possessions of Major Jesse Marcel undergoes a crucial test. As a US Army intelligence officer, Marcel was the first government official at the crash site. Investigator Ben Smith is taken to a secret location believed to be the real resting place of the airborne object, as a local archeologist finds evidence that a military cleanup may have taken place. A leading code-breaker continues his attempt to decipher the journal which may be written in a home-brewed code and contain hidden information about what happened at Roswell. And witnesses describe a series of bizarre events surrounding the now legendary crash, while an incredible new technology attempts to read words on a 70 year old photograph that may hold clues to the mystery: Did an extraterrestrial spaceship crash at Roswell?

Investigator Ben Smith travels to Jesse Marcel's hometown on Louisiana's Gulf Coast to speak with family members who reveal information that supports Marcel's story of a government coverup. Smith speaks with Leslie Kean, the investigative journalist who broke The New York Times story about a clandestine U.S. government program to investigate UFOs. Smith also digs deeper into the mystery of the journal as he studies writing samples to determine if the journal might have been written by one of Marcel's fellow officers who later claimed he was ordered to oversee the military's coverup. Back in Marcel's hometown, Smith meets with a man who swears Marcel confided in him about alien bodies-- something Marcel had never mentioned to the press or family. As the results come back from soil, metal and forensic handwriting analysis, Smith shares his findings with the Marcel grandchildren.

On December 5, 1945, five American WW2 torpedo bombers took off from Florida with all men and planes disappearing without a trace. Hours later, the search plane dispatched to find them, also vanished, believed to be lost to the infamous Bermuda Triangle. The number of men tragically lost that day totaled 27 and 75 years later, it remains an unsolved mystery. No ship in history has searched the extreme depths of the Bermuda Triangle, thought to have claimed over 1,000 ships and planes, until now. The late Paul Allen's ship, R/V Petrel, the most advanced search vessel of its kind, will deploy a wide array of cutting edge technology including deep-diving submersibles to investigate three miles down, in an effort, to find the lost squadron and solve the mystery that began the legend of the Bermuda Triangle.

An investigation into the unshakable claims of Roger Miklos, one of America's most eccentric, controversial, and accomplished treasure hunters. Decades before his death in 2018, Roger believed he discovered a modified Nazi U-boat loaded with a fortune in artwork, antiquities, and gold off the coast of Turks and Caicos. Before he passed, Roger gave an exclusive interview that revealed clues about the possible position of the U-boat and left behind a trove of documents, maps, and photographs. Now, armed with this evidence, celebrated diver Mike Fletcher and his team will take to the high seas in search of the special U-boat.

One of World War II's greatest unsolved mysteries: an incomparable work of art worth half a billion dollars, lost without a trace. Perhaps the single most valuable object the Nazis ever stole, the quest for this treasure has lasted over 75 years. Where is the famed Amber Room? And will a brand-new search finally reveal its true location?

It's a treasure coveted by everyone from Roman Emperors to Adolf Hitler--a sacred object said to hold incredible powers of healing, resurrection and immortality. It may be the world's most sought-after relic, but what is the Holy Grail? And if it exists, can it ever be found?

One of the holiest and most powerful relics from the Bible has been missing for over 2,000 years. While some believe the Ark of the Covenant was destroyed, many people think it's still out there. Could new clues finally tell us what happened to the Ark, and lead us to where it can be found?

In 1930, a New York Supreme Court justice with close ties to Tammany Hall, and future president Franklin Delano Roosevelt, steps out of a steakhouse and disappears. For decades, the politically charged case dominates mainstream media and remains unsolved nearly 100 years later. But could a deathbed confession finally tell us what really happened to the notorious Judge Joseph Crater?

One of history's most notorious pirates, Blackbeard, is said to have had a treasure worth millions of dollars. After centuries of searching, the legendary hoard remains missing. As new evidence is unearthed, the mystery endures: what became of Blackbeard's lost treasure?

An ancient mechanical device found on a 2,000-year-old shipwreck has become known as the world's first computer. The machine is centuries more advanced than historians thought possible, but its origin and true purpose are shrouded in secrecy. Can modern technology finally unveil what the mysterious Antikythera Mechanism actually is?

Awe-inspiring and mysterious, the pyramids of Egypt are significant wonders of the ancient world; more than 4,000 years old, they are celebrated architectural marvels, but no one fully understands how they were built or why.

It's one of the most famous stories from the Bible; for thousands of years the tale of Noah's Ark is shared, but little is known about what happened to the ark.

It's the only unsolved air piracy case in history; in 1971, a man hijacks a Northwest Orient Airlines flight, demanding four parachutes and $200,000; he jumps out of the plane with the money and is never seen again.

She was the last pharaoh of Egypt and one of the most famous queens of all time, but her death in 31 B.C. has been shrouded in mystery. Cleopatra's body and final resting place have been lost without a trace for over 2,000 years, leaving the world's top archaeologists baffled. Can new evidence finally uncover Cleopatra's missing tomb?

In a perfectly planned robbery, thieves steal half a billion dollars in masterpieces from the Gardner Museum in Boston; it's been three decades since the brazen heist, and an exhaustive search has failed to recover the stolen goods.

An Aztec king's glittering treasure vanishes into thin air, inspiring a 500-year search that spans continents; one of the greatest warriors of all-time amassed a vast horde believed to be worth more than $3 billion today.

Most people know it as the biblical birthplace of man -- the Garden of Eden; investigating if the Garden of Eden was just a story to explain human creation or if it was a real place.

A look at what happened to the secret hoard of the Knights Templar, a treasure of gold, silver, gems and religious relics protected by a medieval religious order.

It's a mystery from the golden age of piracy. In 1698, Captain William Kidd raids a ship on the high seas and seizes its vast treasure... but Kidd is hanged before revealing where he stashed the loot. What happened to Captain Kidd's lost booty... and where is it now?

With 500-year-old secrets hidden in skeletons and stone, Machu Picchu is one of the most puzzling archaeological sites on earth. It's among the ancient world's most enduring riddles: Who built this astonishing complex, and why?