Ciphers
Featured — award winners and classics first, when available. Use “Show different books” for a new selection.
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Into the Gauntlet
The Cat's elbow and other secret languages
Speaking secret codes
Margaret Moncrieffe; the first love of Aaron Burr
I spy
Addison Cooke and the Treasure of the Incas
Top-secret code book
Top secret!
Codes and ciphers
Will Solvit and the mission of menace
The Unbreakable Code
Secret Language
Morse code
Enigma
Finding Paris
The Emperor's Code
Mishneh Torah (Codification of Talmudic laws)
Top secret
Tower of secrets
Alvin's Secret Code
The Lost Symbol
The Medusa plot
The Viper's Nest
Spy codes and ciphers
Hieroglyphs for fun
How to keep a secret
The knowhow book of codes, secret agents & spies
Sly the sleuth and the code mysteries
The Hut Six Story
The master spy handbook
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