History's Greatest Mysteries Season 6: Episode Guide & Ratings

It's one of America's most mythic UFO incidents. A 200 yard swath of debris that landed near Roswell, New Mexico. Some believe it was an alien craft, others that it was a secret government experiment. The deeper researchers dig, the more perplexing the story gets. It's a mystery that's endured for nearly 80 years. So what really crashed in Roswell in 1947?

The search for the illusive Northwest Passage, leads to a historic expedition that sets sail into a labyrinth of ice and is never heard from again. That disappearance sparks a search for clues spanning nearly two centuries and leads to unthinkable ends. What really killed the men of the Franklin Expedition?

On February 14th 1929, one of the most shocking murders in mob history goes down in Chicago and becomes known as the Valentine's Day Massacre. The 20s and 30s are full of gangland murders, but the Valentine's Day Massacre is considered the most brutal and the toughest to solve. So who carried out the Valentine's Day Massacre and why?

Sightings of the Yeti, a creature of myth and legend, have been recorded for thousands of years throughout the Himalayas and surrounding regions. Could this seven foot tall creature, covered in shaggy gray hair, be hiding in plain sight? And if the Yeti does exist, is it a living being or something else entirely?

Amelia Earhart, the world's most famous female pilot, takes off on the final leg of a record breaking flight. But Earhart never arrives at her next stop, a tiny island in the Pacific Ocean. The search for this famed flier has revealed conflicting stories and in the eyes of some, secrecy. What really happened to Amelia and her navigator?

Pablo Escobar, the notorious narco trafficker who single handedly supplied most of America's cocaine in the 1980s, had billions of dollars in cash and hid stacks of it all over the country. By the time he was gunned down in 1993, it's believed he was worth over $50 billion in today's money. To some, he was a Robin Hood. To others, he was pure evil. Who killed Pablo Escobar and where did all his money go?

Cash, jewels and two million dollars in gold bars. Jesse James and his gang robbed trains, stagecoaches and banks They buried the spoils, but only a fraction of the millions has actually been found. If James and his gang hid a fortune, where could it be?

A surreal event outside a U.S. Air Force base near the Rendlesham Forest in England, becomes an international legend and one of history's strangest unidentified encounters. For more than 40 years, the question has endured... What was really out there in the Rendlesham Forest and what were the Rendlesham lights?

The Burning Bush, the 10 Plagues, the Parting of the Red Sea... these legendary Biblical events in the Book of Exodus have shaped Judeo Christian beliefs for centuries. But were these events divinely inspired miracles, or do they have a more earthly explanation? Is it possible that some of these famous legends in the Book of Exodus, aren't parables... but rooted in fact?

It's history's most famous lost city... Atlantis, the island kingdom that's baffled explorers for centuries. Some say Atlantis is a myth, while others insist it was a very real place wiped out thousands of years ago. Finding Atlantis would not only be the archaeological coup of this century, but perhaps for all time. Is Atlantis a a real place, and if so, where could it be?

He was the first Public Enemy Number One... the legendary outlaw, John Dillinger. His life consisted of brazen bank robberies across the country, but his death remains shrouded in mystery. What really happened to John Dillinger?

The legendary ancient ruler who amassed a fortune estimated to be worth 120 trillion in today's dollars, Genghis Khan, hid his riches so well that to this day, no one has unearthed them. 800 years later, the fate of his treasure remains a mystery. Where are Genghis Khan's buried riches?

Nicola Tesla is the epitome of what some would call the "mad scientist" and also one of history's most influential inventors. The father of AC electricity, Tesla had revolutionary ideas--but in the hands of the wrong people, those ideas could be used for evil purposes. When Tesla died, he allegedly had 80 trunks of papers full of groundbreaking ideas. But only 60 of those trunks have ever been seen again. Where are the other 20 trunks? What happened to Tesla's missing files... and what was in them?

This is the most mysterious of the Dead Sea Scrolls. An ancient treasure map, recorded on a rare Copper Scroll, could lead to billions of dollars of buried treasure in gold, in silver, in jewels, hidden away thousands of years ago from Roman invaders. The most mysterious of the Dead Sea Scrolls; The clues listed on the Copper Scroll could lead to this vast fortune. Where is the secret treasure of the Copper Scroll?

It's one of the most infamous and unsolved mob murders--notorious mobster Bugsy Siegel is gunned down in his Beverly Hills living room.

One of the most famous explorers in the world, Percy Fawcett, becomes obsessed with a lost city deep in the Amazon jungle, a place he names the City of Z.

Rising from the sands of the Egyptian desert is one of the ancient world's greatest wonders--the mighty Sphinx. This mythological creature, with the head of a human and the body of a lion, looks like it's standing guard at the great pyramids of Giza.

Known as :The Terror of the Gulf"; the whereabouts of Jean Lafitte's treasure remains unknown; the swamps and bayous were his base, and likely also his hiding place; treasure hunters have found very little of Lafitte's stash.

The gigantic statues of Easter Island have mystified humanity for centuries; how in the world did an ancient civilization, with only primitive tools, carve and then move thousands of these rock monuments around the island, and why?

The Tower of Babel, Sodom and Gomorrah, and Mount Sinai have seemingly vanished from the map; where are the Old Testament's legendary lost places, and what might they reveal?