It started in 1698, when a prisoner using the pseudonym Eustache Dauger (which on paper looks heroically similar to "Mustache Danger") was transported to the Bastille, the 17th century French equivalent of a maximum security prison. He had already spent between two and three decades (old-timey records are, at best, imprecise) rotting in various jails across the country. According to legend, he showed up already locked in the iron mask (which looked like an Iron Man Mark I helmet) and was immediately tossed in a cell, forbidden to speak to anyone except to ask for food, water, or a pot to make poopies.

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"OK, I filled the pot. Now can I have my stale bread and water?"

And ... that's all we know. Nobody discussed who the hell he was or what he had done or why he needed to be dressed like a very lazy knight. He was listed in the Bastille records as "Prisoner 64389000," which, in addition to being difficult to fit into a song, is a completely sterile piece of information. He was forbidden to ever show his face to anyone, and some prisoners claimed he had two armed guards with him at all times should he ever try to take the mask off. In that event, we assume they would aim for his chest, or shove their musket barrels into his iron eyeholes.

Dauger (or whatever his name truly was) died in 1703, which, as keen-eyed readers may notice, means he sat in the Bastille with his head in a fucking crock pot for four dick-punching years. The subsequent 300 years have done nothing to uncover the mystery of his identity, either -- there were few solid facts about the man to begin with, and three centuries of retellings laced with spirited embellishments have seriously diluted what little we had to go on.

Biography
At least they permitted him the dignity of shoe and knee bows.

The popular theory is that he was some kind of high-level political prisoner, hence the need to conceal his identity. However, nobody can quite agree on exactly who that famous inmate might have been, with some of the wilder guesses ranging from Oliver Cromwell's son to the older brother of King Louis XIV himself (Dumas' novelization of the DiCaprio movie is based on that second idea). All we really know about him is from letters written by the Bastille's governor and from his fellow prisoners spreading the story, and those testimonies are contentious about whether his mask was even made of iron to begin with. To be fair, "The Man in the Black Velvet Vanity Veil" doesn't carry quite the same level of mystery and intrigue.

First, the items scattered around her body might as well have been arranged to spell "ambush murder" on the ground next to her. Bottles of gasoline and liquor, a mostly incinerated passport, and enough sleeping pills to kill a Hollywood screen legend were found close enough to have been hastily dropped by a stab-bandit upon hearing the echo of approaching footsteps. But the Isdal Woman herself was difficult to identify, immolated remains notwithstanding -- her fingerprints had been sanded away, and apart from evidence of some work that might have been done in Latin America, her dental records returned no matches.

It seemed like investigators had caught a break when two of her suitcases were discovered in a safety deposit box at a train station, but all of the clothing packed inside had been stripped of their labels. There was a prescription bottle, but the identifying label that might have contained her name and address had been peeled off. In addition, the police found several fake passports adorned with entrance stamps from Moscow (this was back during the Cold War, so fake passports from Russia were highly suspect), and there were 500 deutschemarks sewn into the lining of one of the bags. She also apparently wore a collection of wigs and wrote notes to herself in code. Either she was James goddamn Bond or her murderer was playing an elaborate practical joke.

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A woman who travels the world under an assumed name with a collection of wigs? Sounds mighty suspicious.

Furthermore, despite a pool of over 100 eyewitnesses who all claimed to have seen her on the days leading up to her death, nobody could agree on anything except a general description of what she looked like, which usually boiled down to some variation of "an attractive foreign lady in her 30s or 40s." She might have been German, or Italian, or French, or she just might have known how to speak those languages. She used a handful of different names, all fake, during her stay in various hotels around Norway, and the primary witness, an Italian photographer who had dinner with the Isdal Woman before she died (and who had previously been questioned in an unrelated rape case), said she was an antiques collector from South Africa on a sightseeing trip, but he couldn't remember any useful details.

Michal Kowalski/Photos.com
"She liked dousing herself in lighter fluid and smoking cigars. D'ya think that might be relevant?"

She was last seen hiking in evening wear (which, generally speaking, is not the attire one selects to go traipsing through a rocky forest of mystery in the middle of the night), being closely followed by two large men in black clothing. Her body was discovered a few days later, burned to a cinder, laced with alcohol and sleeping pills, and with evidence of blunt force trauma on the back of her neck. The police were so baffled by every single facet of the case that they literally gave up, ruling the Isdal Woman's death a suicide because, hey, why not.

All we know is that he went by the code name Perseus. He was in place from 1943 to 1946, nearly the entire duration of the Manhattan Project. And unlike other Soviet moles, who were quickly discovered once World War II came to an end, the Americans had no idea that Perseus even existed until some former KGB officials spilled the beans in 1991. The man stole some of the most sensitive secrets the U.S. government has ever kept and went tap dancing off into the sunset for almost 50 years before anybody realized he'd taken anything.

According to secret KGB documents that were decrypted during a code-breaking project known as Venona (because cryptographers specialize in nonsense words), Perseus was among the high-level scientists at the White Sands missile testing site in New Mexico, as well as the main research facility in Los Alamos, which means he had firsthand access to pretty much everything. The information he gathered (along with that collected by the three spies who eventually got busted) not only gave the Soviet Union an extra year's head start to develop their own nuclear program, but also gave Josef Stalin enough time to practice his "I'm totally surprised" face for when President Truman revealed the atomic bomb to him at the Potsdam Conference in 1945.

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"I knew about nuclear superweapons before they were cool."

Several prominent scientists have been accused of being Perseus, but every one of them was able to categorically prove his innocence. In addition, the Russians suddenly blocked access to all of their declassified archives almost as soon as they had granted it, and the records have remained closed ever since. Whoever Perseus was, he must certainly be dead by now. The only possible reason to keep his identity a secret is if he's some kind of deathless nuclear supermutant who's spent the past half-century maneuvering his way into the highest levels of Russia's political infrastructure.

And not only does nobody know who he was, but nobody is even sure if any of the shit he wrote was actually true.

Charles Johnson makes it very clear on the cover of Notorious Pirates that he is a pirate captain, and the book's text maintains this assertion throughout. In a time when fake biographies were circulating the world like counterfeit postage stamps, his was the first authentic account of daily pirate life that anyone had ever seen (in the book's bizarre third-person introduction, Captain Johnson more or less dares anyone reading to call him a liar). And he provides stories, anecdotes, and insights that only someone with firsthand experience would be able to relate. He even had candid woodcuts of piratical life -- the lonely sea captain equivalent of photographic evidence.

National Science Foundation/MilitaryTimes
"Keep the boat steady while I whittle this. Nobody will believe us otherwise."

The problem is that there were no pirates named Charles Johnson operating during that time period. Also, and perhaps more incriminating, there's the fact that virtually no pirate in the history of time had any kind of higher education. Illiteracy was so emphatically the norm among pirate crews that we are surprised none of them used pictographs to label their booty, and yet whoever was responsible for Johnson's book clearly knew how to read and write.

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"Arrrrr ... is a letter I can neither write nor recognize."

The most popular theory is that Captain Charles Johnson was actually Robinson Crusoe author Daniel Defoe, doing an undercover buccaneer expose. However, if that's the case, we're disappointed in him for having selected the most unimaginative pirate name in recorded history.

For some inexplicable reason, Traven went to incredible lengths to keep his identity a secret. In fact, B. Traven wasn't even his real name, which shows you how serious he was about the deception. It was a pen name he selected before beginning his writing career in Europe -- most of his books were published in German first, then translated into English later. Understandably, this has led many people to believe that Traven was German, despite the fact that during the first half of the 20th century, Germans were primarily occupied with killing people and not writing things.

Utilizing his fake name of make-believeitude, Traven wrote in Europe for several years before relocating to Mexico, which, considering the European climate at the time, was probably a smart move. He avoided going out in public as much as possible and would submit his manuscripts either via mail or through a proxy/human decoy, as if he was fearful of being struck down by assassins' bullets at any given moment. He was so good at this that only a handful of photos of Traven are known to exist, one of which was taken when he was arrested in London for forging travel papers because he didn't want to give out any personal information.

Wikimedia Commons
If you're going to be weird, just do it honestly.

Even after B. Traven died in 1969, reporters continued hounding his longtime associate and translator Hal Croves to reveal the author's true identity, even going so far as to ask if Croves himself was the famous recluse (in fact, "Traven Croves" was the alias Traven was using at the time of his death, so this wasn't exactly a leap of deductive reasoning). So who was he?

One theory points to a German actor named Ret Marut, who changed his name to the less G.I. Joe-sounding B. Traven to escape imprisonment during the German Revolution, which, contrary to popular belief, was a thing that happened. Other theories claim that Traven was an illegitimate son of Kaiser Wilhelm, that he was actually two or more people joining forces as a literary Voltron, or that he was an alter ego of the famous novelist Jack London, because Jack London liked to write a bunch of weird bullshit about being outside, too.

Wikimedia Commons
Yup, the guy with the Hitler mustache might have had this guy as a father. Seems appropriate somehow.

WARNING: This is going to be the weirdest goddamn story you've heard all week.

In the 1880s, a young woman was found floating in the Seine River in Paris. It was exactly like the beginning of The Bourne Identity, if that movie had been 10 seconds long and about drowning. The police fished her body out of the water and sent her off to the coroner, because the 19th century was a time when investigative techniques went about as far as checking the immediate area for evil spirits and then going back to the police station to wait for someone to confess to the crime. The coroner became smitten with the corpse and took her body straight to a molder to have a plaster cast made of her dead face, because everything was terrifying back then.

Mental Floss
"This was actually the third least terrifying thing we could have done with her body."

Before the coroner could come back to pick up his plaster corpse mask, random customers in the molding shop took notice of the piece and began requesting duplicate casts of their very own. Because money often helps you ignore the pleas of your conscience as it is torn apart by foul wrongness, copies of the anonymous dead girl's face were soon mass produced. By the turn of the century, the mask was a must-have across France and Germany, which are a pair of countries that know a thing or two about horrifying craziness.

The fad mercifully waned, but the masks could still be found all over Europe. So when the first CPR dummy was created by a Norwegian toy maker back in 1960, he decided to base its face on the Woman of the Seine's famous lifeless fear helmet, because why the fuck wouldn't he? Every single rescue dummy manufactured since then has had her face, which means that if you've ever been a lifeguard or had to take CPR training in high school, you have wrapped your lips around the mouth of a 130-year-old dead girl. And to this day, nobody has any idea who she was, so odds are she's haunting at least one of us right now.

Scientific Equipment Liquidators
Hey, look at the bright side, mystery lady -- you've probably gotten more mouth action than anybody else in history.

Evan V. Symon is a moderator in the Cracked Workshop. When he isn't trying to find the real identity of Banksy, he can be found on Facebook, and be sure to bookshelf and vote for his new book, The End of the Line.

For more unusual tales, check out 6 People Who Just Fucking Disappeared and The 5 Creepiest Unsolved Crimes Nobody Can Explain.

If you're pressed for time and just looking for a quick fix, then check out The New Movie That Is Clearly a 'Men in Black' Rip-Off.