If you're a teenage boy then you're probably familiar with /b. For the rest of us, a quick explanation is in order. The short version is that 4chan/b is a popular image board where people post all sorts of random stuff. Most 4chan/b users post anonymously which is a strong indicator of the typical content you can find there. The site is known for being, um... juvenile, irreverent, unexpected, hilarious, brilliant, disturbing, offensive, etc.

4chan tends to attract both those who are not nearly as smart as they think they are as well as some who are far smarter than they think they are. Both groups are usually young and tend to have a certain non-conformist attitude. If you were the leader of a secretive underground group of anarchists and you wanted to recruit some highly intelligent hackers with a tenuous respect for authority then 4chan might be a good place to look for potential members. All you'd need is some way to separate the budding geniuses from the incorrigible delinquents.

On January 4th, 2012, an anonymous user posted an odd image on /b and /x, the paranormal cousin of /b. While odd images on 4chan are not at all odd, this image was different. This image contained a message which was the beginning of an astoundingly complex and mysterious puzzle. Such an odd message could easily have been lost in the endless stream of noise that is 4chan but a few people noticed it. Those first few were like Alice wondering where the rabbit hole leads except this time the adventure was real. The mystery is known as Cicada 3301 and it may have started in the strange world of 4chan but it quickly became highly technical and has moved far beyond the realm of the average 4chan user or typical ARG.

Many have claimed that they solved all the clues and reached the end of the puzzle but nobody has provided proof. Solutions that are shared are inevitably posted anonymously and missing the digital signature that would prove authenticity. This lack of proof doesn't necessarily mean the solutions are fake but the entire mystery revolves around public-key encryption and Internet security so the lack of proof is a rather glaring omission.

Much more vexing are the unexplained disappearances. It is disturbingly common for someone to get close, publicly discussing their progress the entire way, then suddenly go silent right at the end. Of course it's possible that they just got busy at work, or got frustrated and gave up, or got bored and went back to playing Pokémon. It's also important to note that some of the early clues encourage cooperation while some of the later clues explicitly forbid sharing the solutions. So maybe these unexplained disappearances are simply participants who have agreed to keep the secret.

Still, it's the Internet, you'd think that eventually someone would be unable to keep a secret. Surely someone would be eager to brag about being the first to solve the mystery. The Cicada 3301 puzzle has received so much press that if someone had the solutions and could prove it, they might be able to sell their story to a variety of journalists. So far though, if anybody has made it to the end, they are staying quiet.

While this mystery has been written about many, many times, very few articles offer much more than second-hand stories and overly dramatic conjectures. That's understandable because dwelling on technical details is a quick way to lose readership. Drama and speculation sells far more advertising than boring minutiae about JPEG compression and TOR servers.

Beyond hyperbolic "journalism" there are also discussion groups and public repositories with piles of information about Cicada 3301. Unfortunately, these rarely explain anything clearly and are often overflowing with banal chatter and intentional misinformation. It can be a bit like trying to learn rocket science by attending UFO conventions.

I enjoy the technical details of puzzles like this and I don't care if readers get bored so I have taken the time to sort through all the nonsense and verify as much of the story as I can. Of course there will be plenty of speculation too but hopefully we can keep it based on the technical details rather than what generates clicks and sells advertising space. If you're a technical type person who likes puzzles, I'll try to present the clues in a way that allows you to solve them yourself. If you'd prefer to skip past all the nerd stuff, you can do that too. Either way, it's a fascinating story so keep reading.

Original Image

It has been long enough now that the original image is somewhat difficult to find. I am 99% confident that the version shown here is an exact copy of the original.

I first saw this image in January 2013, shortly after a second mysterious image had appeared on 4chan. A single instance is a fluke but two instances suddenly looks like a pattern. Indeed, nearly every year since, a new Cicada 3301 puzzle has appeared on or around January 4th. Every year's puzzle is different and, as far as the public knows, they're all unsolved.

As we'll see, the puzzles don't remain active indefinitely. Some clues interact with the real world and have long since disappeared. Some clues were specifically designed with time limits, purposely only letting the first few people through. The original puzzle is long expired now and impossible to solve completely. It's still an interesting story though and it's fun to try to solve the pieces that are still intact.

Let's start at the beginning. On January 4th, 2012 the mysterious picture was posted to 4chan. The message seems straight-forward enough, it's a test to find "highly intelligent individuals." All you have to do for the first step is find the message hidden in the image.

Any ideas? You can right-click to download the image and play with it yourself. I promise it's safe and not some kind of trick or anything bad.

Don't go to the next page until you're ready for the answer. If you think you might be able to figure it out but you're not sure, click on the Hint button. If the hint makes no sense then there's a good chance this puzzle isn't for you. No worries, all that means is that you're not nerdy enough, congratulations.