Unsolved Crypto Mysteries

A cigarette case from 1909 bears a mysterious engraved inscription.

Ignatius Pollaky, a 19th century private detective, published several encrypted newspaper ads. They have never been solved.

A postcard, sent by football official George Furlong from Luton, England, to his sister Lizzie in 1873, has never been solved.

Five encrypted messages from Nazi spy Walter Köhler are still unsolved.

A copper-and-stone sculpture at the headquarters of the CIA featuring four encrypted messages, one of which remains unsolved.

A code appears to be hidden in the end credits of the 2010 movie Fair Game.