"Hello. We are looking for highly intelligent individuals. To find them, we have devised a test. There is 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."

That message, signed "3301," appeared on the underground message board known as 4chan two years ago. It was mysterious, cryptic and sparked a global Internet mystery that has yet to be answered to this day.

Thousands of people took on the challenge.

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. Hidden inside that first seemingly simple image — those black words on white text — were many more pictures, codes, clues and the reoccurring image of a cicada. That's what gave the mystery its name: Cicada 3301.

AeolianWLOP