History Main / TheBookCipher

Big and well-known books make better sources as you have more words to choose from (thus Literature/TheBible is often the source), and no one will react if you're walking around with a pocket version of ''Literature/TheDaVinciCode''. Relatedly, if you are unfortunate enough to lose your copy, a well-known book will be easier to replace without raising eyebrows, though some books are slightly different from edition to edition, so you need to make certain to get the right one (This also applies to the Bible, as the New Testament is an English translation of a collection of Latin and Latin-translated Greek documents, and the Old Testament is an English translation of a Latin translation of a collection of Hebrew documents. Better make certain you specify which version you want, as exact word choice can vary considerably between versions even if the general meaning of any given verse stays roughly the same). If you're walking around with an 1824 edition of a book, or asking specifically to buy a copy of the fourth printing of the second edition of something... people may well get suspicious (especially the detective who's after you). Of course, using a widely available book also makes it easier for other people to read your messages, should they be intercepted, and while the book itself may be utterly innocuous, sending a letter that is merely a long list of numbers is an unmistakeable indication that you are communicating in code.

* Creator/{{Graham Greene|Author}}'s heroes often use book codes. In ''The Human Factor'', several books are used, and an edition of Charles Lamb's ''Tales from Shakespeare'' is used in ''Our Man in Havana''.

* ''Series/{{Castle}}'': In the episode "Tick, Tick, Tick..." a serial killer taunts police with a message encoded in what Castle figures out is a book cypher, based on his latest Nikki Heat novel.

* {{Series/Castle}}: In the episode "Tick, Tick, Tick..." a serial killer taunts police with a message encoded in what Castle figures out is a book cypher, based on his latest Nikki Heat novel.

* Several novels in the TabletopGame/BattleTech universe use this, as it is one of the few ways that messages can be sent that [[PathOfInspiration ComStar]] is unable to break. It is mentioned in one example that the book used was fairly common, but it was a specific rare printing of it that allowed them to block decryption.

* Another Wimsey example at one remove is in ''Have His Carcase'', using a [[http://www.simonsingh.net/The_Black_Chamber/playfaircipher.htm Playfair Cipher]] with the keyword (the tenth word on page 583 of the latest edition of a Chambers' Dictionary) disclosed this way.

-->''In your example, the first word of the deciphered message is "[[GratuitousGerman Auf]]"[[note]]on[[/note]] but ours had come out "Heu"[[note]]hay[[/note]]!''

* The [[http://simonsingh.net/media/articles/maths-and-science/the-beale-treasure-ciphers/ Beale Ciphers]] are possibly a case of this. At the least, the second of the three documents, the one indicating the contents of the treasure, maps to the letters in the Declaration of Independence. Of course, there's also some evidence that [[http://www.criticalenquiry.org/beale/beale.shtml it was a hoax from the start]].

* A ''ComicBook/DetectiveComics'' story "And the Executioner Wore Stiletto Heels" (issue #630) involved the villain, Stiletto, using an obscure book about shoes for a cipher (the villain chose this book as a pun on his name--think "stiletto heels"). When Batman goes to the bookstore, the owner mentions how strange it is that he just sold several copies of a book nobody would buy normally. Batman asks him who bought the book in order to learn who's in on the plot.

Big and well-known books make better sources as you have more words to choose from (thus Literature/TheBible is often the source), and no one will react if you're walking around with a pocket version of ''Literature/TheDaVinciCode''. Relatedly, if you are unfortunate enough to lose your copy, a well-known book will be easier to replace without raising eyebrows, though some books are slightly different from edition to edition, so you need to make certain to get the right one (This also applies to the Bible, as the New Testament is an English translation of a collection of Greek documents, and the Old Testament is an English translation of a Greek translation of a collection of Hebrew documents. Better make certain you specify which version you want, as exact word choice can vary considerably between versions even if the general meaning of any given verse stays roughly the same). If you're walking around with an 1824 edition of a book, or asking specifically to buy a copy of the fourth printing of the second edition of something... people may well get suspicious (especially the detective who's after you). Of course, using a widely available book also makes it easier for other people to read your messages, should they be intercepted, and while the book itself may be utterly innocuous, sending a letter that is merely a long list of numbers is an unmistakeable indication that you are communicating in code.

* In ''Literature/TheValleyOfFear'', SherlockHolmes decrypts a message enciphered with a book cipher by deducing which book had been used as a key text, though he does get messed up at one point because the letter was written at the turn of the year and the cipher key was an almanac, resulting in Holmes' first guess as to which edition of the almanac to use being wrong.

* Benedict Arnold tried to use these while plotting his defection to the British.

* The film version of ''Film/RedDragon'' has the serial killer and Hannibal Lecter communicate by posting a notice in a tabloid personal section. To pass a hidden message this way, verses from Literature/TheBible are listed. The FBI recognizes that some of the verses don't exist, and are actually an example of this trope; the chapter:verse numbers correspond to page and word in Lecter's copy of ''The Joy of Cooking''.

* The film version of ''Film/RedDragon'' has the serial killer and Hannibal Lecter communicate by posting a notice in a tabloid personal section. To pass a hidden message this way, some bible verses are listed. The FBI recognizes that some of the verses don't exist, and are actually an example of this trope; the chapter:verse numbers correspond to page and word in Lecter's copy of The Joy of Cooking.

Big and well-known books make better sources as you have more words to choose from (thus Literature/TheBible is often the source), and no one will react if you're walking around with a pocket version of ''Literature/TheDaVinciCode''. Relatedly, if you are unfortunate enough to lose your copy, a well-known book will be easier to replace without raising eyebrows, though some books are slightly different from edition to edition, so you need to make certain to get the right one (This also applies to the Bible, as the New Testament is an English translation of a collection of Latin documents, and the Old Testament is an English translation of a Latin translation of a collection of Hebrew documents. Better make certain you specify which version you want, as exact word choice can vary considerably between versions even if the general meaning of any given verse stays roughly the same). If you're walking around with an 1824 edition of a book, or asking specifically to buy a copy of the fourth printing of the second edition of something... people may well get suspicious (especially the detective who's after you). Of course, using a widely available book also makes it easier for other people to read your messages, should they be intercepted, and while the book itself may be utterly innocuous, sending a letter that is merely a long list of numbers is an unmistakeable indication that you are communicating in code.

Big and well-known books make better sources as you have more words to choose from (thus Literature/TheBible is often the source), and no one will react if you're walking around with a pocket version of ''Literature/TheDaVinciCode''. Relatedly, if you are unfortunate enough to lose your copy, a well-known book will be easier to replace without raising eyebrows, though some books are slightly different from edition to edition, so you need to make certain to get the right one (This also applies to the Bible, as the New Testament is an English translation of a collection of Greek documents, and the Old Testament is an English translation of a Greek translation of a collection of Hebrew documents. Better make certain you specify which version you want, as exact word choice can vary considerably between versions even if the general meaning of any given verse stays roughly the same). If you're walking around with an 1824 edition of a book, or asking specifically to buy a copy of the fourth printing of the second edition of something... people may well get suspicious (especially the detective who's after you). Of course, using a widely available book also makes it easier for other people to read your messages, should they be intercepted, and while the book itself may be utterly innocuous, sending a letter that is merely a long list of numbers is an unmistakeable indication that you are communicating in code.

* ''[[Literature/{{Safehold}} By Heresies Distressed]]'': A group of Temple Loyalists uses a four-number book cipher (page, paragraph on that page, sentence in that paragraph, word in that sentence) to plot Sharleyan's assassination. While the cipher itself was devised by the Church centuries earlier, one plotter notes the irony that Charis' "heretical" introduction of Arabic numerals [[note]]pre-Merlin Safehold used Roman numerals[[/note]] makes the cipher much easier to use.

* Creator/GrahamGreene's heroes often use book codes. In ''The Human Factor'', several books are used, and an edition of Charles Lamb's ''Tales from Shakespeare'' is used in ''Our Man in Havana''.

* ''[[Literature/{{Flashman}}'' Flashman and the Mountain of Light]]''. Flashman gets a nasty shock when he's LuredIntoATrap by a false message while working undercover in India. First they captured and tortured the courier who passed on his messages, then brought in a cryptographer (cryptography is an Indian invention, as they point out) to crack the code, getting all the evidence they need.

[[folder: Alternate Reality Game ]]

* In ''Lost: Mystery of the Island'', a series of four jigsaw puzzles released in 2007, Ottendorf cipher was used on each puzzle's box to hide spoilers and reveal information about the show to the fans.

[[folder: Anime and Manga ]]

* In ''Manga/{{Naruto}}'', Jiraiya uses a book cipher referring to his own novels to convey information about Pain.

[[folder: Comic Books ]]

[[folder: Film ]]

[[folder: Literature ]]

[[folder: Live Action TV ]]

[[folder: Tabletop Games]]

[[folder: Western Animation ]]

* One episode of ''{{WesternAnimation/Cyberchase}}'' used this, using a cookbook with the page-line-word code. Once the main characters find out that Hacker has a copy of the book and is using it to decode their messages (with no real explanation as to how he figured out what kind of code they were using and what book was the key), they quickly come up with a new code. Clueless Hacker still thinks the code is the same when he intercepts the new message.

[[folder: Real Life ]]

* In ''{{Naruto}}'', Jiraiya uses a book cipher referring to his own novels to convey information about Pain.

* A book cipher plays an important role in the TV version of ''Series/{{Sharpe}}'s Sword''. The key text is [[spoiler:Voltaire's ''Literature/{{Candide}}'']].

* A ''[[Franchise/{{Batman}} Detective Comics]]'' story "And the Executioner Wore Stiletto Heels" involved the villain, Stiletto, using an obscure book about shoes for a cipher (the villain chose this book as a pun on his name--think "stiletto heels"). When Batman goes to the bookstore, the owner mentions how strange it is that he just sold several copies of a book nobody would buy normally. Batman asks him who bought the book in order to learn who's in on the plot.

John Doe has a copy of a book. Richard Roe has an identical copy of the same book, which he can use to decipher John's coded messages and code his own replies. The messages are written out in groups of numbers; Either the first number is a page, the second number a line on the page, and the third number a word inside that line, or it can also be just the page number and word number, if you want to make it easy. The Ottendorf Cipher is a specific variant that uses Page, Word, and then the letter inside that word, which lets you encode words that aren't found within the text - like, say, the address of a meeting place.

Big and well-known books make better sources as you have more words to choose from (thus Literature/TheBible is often the source), and no one will react if you're walking around with a pocket version of ''Literature/TheDaVinciCode''. Relatedly, if you are unfortunate enough to lose your copy, a well-known book will be easier to replace without raising eyebrows, though some books are slightly different from edition to edition, so you need to make certain to get the right one (This also applies to the Bible, as the New Testament is an English translation of a collection of Latin documents, and the Old Testament is an English translation of a Latin translation of a collection of Hebrew documents. Better make certain you specify which version you want, as exact word choice can vary considerably between versions even if the general meaning of any given verse stays roughly the same). If you're walking around with an 1824 edition of a book, or asking specifically to buy a copy of the fourth printing of the second edition of something... people may well get suspicious (especially the detective who's after you). Of course, using a widely available book also makes it easier for other people to read your messages, should they be intercepted, and while the book itself may be utterly innocuous, sending a letter that is merely a long list of numbers is an unmistakeable indication that you are communicating in code.