For more than 15 years, amateur and professional code-breakers have been baffled by Kryptos, a sculpture at the CIAs headquarters in Langley, VA, that features a nearly 12-foot-tall, copper scroll inscribed with four long, coded passages. The coded passages remained unsolved for eight years, until a CIA analyst cracked the first three in 1999. But the fourth passage is still a mystery.

Interest in solving the final part of the puzzle has soared after the publisher of Dan Browns bestselling novel The Da Vinci Code posted a game on www.thedavincicode.com, which states that numerous encrypted messages on the books dust cover hint at the subject of Browns next novel. The clues, which were not recognized until the game was posted, include a set of geographic coordinates that roughly locate the sculpture. Brown himself has recently hinted that the Kryptos sculpture might play a role in his upcoming novel The Solomon Key.

Deciphering the Passages

Sculptor Jim Sanborn claims to be the only man alive who knows the solution to the final passage. When Kryptos was installed in 1990, Sanborn was required to hand a sealed envelope containing its solution to then CIA Director William Webster. But Sanborn now says that the letter withheld information critical to solving the puzzle.

Sanborn has confirmed the accuracy of the solutions to the first three passages, which contain deliberate misspellings, letters carved slightly higher than others on the same line, and other irregularities that may themselves be clues to solving the fourth passage and possibly for locating something buried. The first deciphered passage reads: Between subtle shading and the absence of light lies the nuance of iglusion [sic].
The second passage, which is followed by geographical coordinates, suggests a location elsewhere on the grounds of CIA headquarters and reads, in part:
It was totally invisible. Hows that possible? They used the Earths magnetic field. The information was gathered and transmitted underguund [sic]to an unknown location. Does Langley know about this? They should: its buried out there somewhere.
The third passage is based on a diary entry made by archaeologist Howard Carter in 1922, on the day that he discovered the tomb of Egyptian pharaoh Tutankhamun. It reads:
With trembling hands I made a tiny breach in the upper left-hand corner. And then, widening the hole a little, I inserted the candle and peered in. The hot air escaping from the chamber caused the flame to flicker, but presently details of the room within emerged from the mist. Can you see anything?
Experts say that the fourth passage is written in a more complex code than the first three, one designed to mask patterns of recurring letters that code-breakers typically look for. There are no breaks in the 97-character sequence of the final passage, which begins with an initial question mark.
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