“Singh spins tales of cryptic intrigue in every chapter.”

— The Wall Street Journal

“Brings together … the geniuses who have secured communications, saved lives, and influenced the fate of nations. A pleasure to read.”

— Chicago Tribune

“Singh pursues the fascinating story [of codes] through the centuries, always providing plenty of detailed examples of ciphers for those who appreciate the intricacies of the medium.”

— Los Angeles Times

“Especially effective at putting the reader in the codebreaker’s shoes, facing each new, apparently unbreakable code.… Singh does a fine job.”

— The New York Times Book Review

“Entertaining.… Singh has a flair for narrative.”

— San Francisco Chronicle

“Singh is an interesting mix of scientist and storyteller, and this subject is the perfect mix of true fact and tall tales.”

— The San Diego Union-Tribune

“Where would we Information Age ignoramuses be without smart guys like Stephen Jay Gould, the late Carl Sagan, or Simon Singh? They are the troubadours of our time, making complicated subjects understandable and entertaining.”

— The Plain Dealer

“In this entertaining survey, the evolution of cryptography is driven by the ongoing struggle between code-makers and codebreakers.”

— The New Yorker

“[Singh] is well-equipped to describe all the arcane mathematics in layman’s language.”

— Forbes

“Wonderful stories.… Close reading is rewarded with the flash of logical insight that the codebreakers must enjoy.”

— Hartford Advocate

“An illuminating and entertaining account.… From the first page, Singh shows his knack both for explaining complex areas of science and telling rip-roaring stories.”

— New York Law Journal

“My only regret is that this great book has come far too late. If only someone had given it to me when I was 10, my secret plans for world playground domination might never have been foiled.”

—James Flint, The Observer (London)

“Full of fascinating case histories covering the development and practical use of cryptography.”

— Mail on Sunday (London)

“Singh has created an authoritative and engrossing read which both explains and humanizes the subject.… This intelligent, exciting book takes its drive from a simple premise-that nothing is as exciting as a secret.”

— Scotland on Sunday