Secret messages, Da Vinci-style codes, keys to predictions and cryptic clues - this giant collection of brain-teasing, enciphered challenges will satisfy puzzle fans at every level. It features over 600 puzzles, from the simple substitution-code type - messages or quotations in code where each letter stands for another - to fiendishly difficult ciphers using actual wartime methods employed by historic figures from Julius Caesar to President John F. Kennedy. There is plenty to challenge the sharpest of minds, and the more you solve, the better and faster you get! You'll find lots of helpful tips and advice on professional ways of cracking codes. Plus there's a fascinating section on the world's most famous unsolved scripts and cryptograms, including the Beale Ciphers, the Kryptos fourth section at CIA Headquarters, the Zodiac Killer ciphers, Emperor Rudof II's Voynich Manuscript and the 3,500-year-old Phaistos Disk.