From Ovaltine's secret decoder badges used during 1940s radio broadcasts to Dan Brown's cipher-solving hero in The Da Vinci Code, secret codes have forever excited the imagination of children and adults alike. Now, The Seven Unsolved Ciphers brings to life the amazing stories and fascinating structures of the secret codes that have stubbornly resisted the efforts of the world's best code-breakers and most powerful decryption software. Readers will follow the horrific story of the Zodiac serial killer and see reproductions of his symbol-filled letters. Could breaking his code lead to the arrest of this still-at-large madman? The method used for breaking the second letter of The Beale Papers is explained, along with the deciphered text, which catalogs a $30 million treasure of gold, silver, and jewels buried somewhere in Bedford County, Virginia. However, it is the unsolved first letter that claims to tell of the underground hideaway where the treasure has remained undisturbed for over a century.