Cicada 3301 is a mysterious organization that gained notoriety for posting a series of highly complex cryptographic puzzles and challenges on the internet, starting in 2012, which have since captivated cryptographers, codebreakers, and conspiracy theorists worldwide. These puzzles, which involved elements of cryptography, steganography, and obscure references to literature and philosophy, were believed to be a recruitment tool for highly intelligent individuals, although the group's true purpose and identity remain unknown.