ARUN RATH, HOST:
And speaking of mysteries, we've got an amazing puzzle for you.
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RATH: No, no, no. Wait, wait, wait. Stop, stop. Not that puzzle. Different show. Look, I don't want to offend, but this is a puzzle that's probably way too complicated for most of us.
CHRIS BELL: It's like a Dan Brown novel, if Dan Brown could write this well, to be honest with you.
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BELL: I mean, it's beyond the realms of my intelligence and beyond the realms, I think, of any individual's intelligence to do this.
RATH: Freeland writer Chris Bell will guide us through this mystery. In a piece for The Telegraph, he wrote about an unknown organization posting incredibly complicated puzzles online to lure the world's most talented code breakers. It began two years ago with a simple message.
BELL: It arrived on an underground message board called 4chan. And the message was a simple black square with white writing on. And the message read: Hello, we're looking for highly intelligent individuals. To find them, we have devised a test. There's a message hidden in this image. Find it, and it will lead you on the road to finding us. We look forward to meeting the few that will make it all the way through. Good luck. 3301. And that was all it said.
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RATH: 3301, the only signature left by the mysterious entity that launched the challenge. Thousands of people took it on. To code breakers who dwell in this world, it was simple in the beginning. The first puzzle used a technique called steganography, concealing a message or image within another image. Terrorists have used it to hide messages. Pedophiles use it to conceal child pornography.
Hidden inside that first seemingly simple image, those black words on white text, were many more pictures, codes, clues and one recurring image, a cicada.
BELL: That's why the puzzle was actually named Cicada 3301, because it just appeared throughout. It's a bit like the moth imagery in Thomas Harris novel, "The Silence of the Lambs." So it began to symbolize the entire puzzle as it started.
RATH: If you decoded that first image, you were led to a website. That website contained more puzzles, even harder ones.
BELL: That's why thousands of people joined in, because no one person had the skills to solve all of the puzzles.
RATH: Extremely obscure knowledge was needed to crack those codes, knowledge of Medieval Welsh literature, occult numerology.
BELL: There was clues placed inside the literature. There was stuff from the Victorian occult. There were Caesar ciphers. There was mind neurology (unintelligible) it led to a telephone number. And when it reached a certain point, they solved clues that led to, I think, 14 different GPS coordinates in locations around the world from a place like Hawaii to Warsaw. And when the people visited these locations, they found the cicada image there again and a further clue.
RATH: This was one of the most complex puzzles the Internet has ever seen.
BELL: And this is why people slowly started to realize that maybe it wasn't just some random, lonely kind of neckbeard sitting in his mom's basement. This was an international game.
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BELL: As the puzzles got more and more complex, people started to, you know, suspect this is a military organization behind this, like, you know, NSA or many people seemed to suspect the CIA behind this kind of thing.
RATH: Some people, working in teams or individually, cracked the code and made it to the end. So what happened?
BELL: Nobody knows. And this is part of the enduring kind of Cicada mystery is that after they got through all these tests the first time around, it led to a website on what's known as the darknet. And this is about the Web that tends to hide various nefarious industries, I think. They led to a website there, which once a certain number of people have accessed it, it closed down and left the message: We want the leaders, not the followers.
And for thousands of people who were trying to solve the mystery, it was an enormous disappointment.
RATH: No one is quite sure what happened for the select few who made it.
BELL: There's lots of different rumors. None of them talked about it. They reckon there's anywhere between a dozen and two dozen people who made it to the final website. Apparently, they had to build a computer server and register certain addresses. But they never realized who - revealed, rather, who was behind the tests to begin with. The path led and stopped.
RATH: But one year ago today on January 5, 2013, it all started over again - the puzzles with different techniques, new physical locations.
BELL: And again, once the first few people got through to that, the website closed down again.
RATH: And the mystery still continues. Chris Bell says it's become something special now.
BELL: It kind of tapped into all the things that the Internet loves, in a way. It tapped into kind of slightly ludicrous conspiracy theory. And then the greatest thing, of course, is it never actually revealed its purpose. For thousands of people who sat at websites to try and decode these puzzles, it's been a real, you know, labor of love for many of them.
RATH: For the past two years, new puzzles appeared online on January 4 or 5. And sure enough, this weekend, a ton of new puzzles appeared. Chris says the problem is so far, all the ones he's checked out have been fakes. But he's going to keep looking.
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