Editing Book cipher (section)

=== In fiction ===

* In ''[[Colony (TV series)|Colony]]'', a television series, the resistance movement uses a book cipher to communicate between members of the cells.
* In the novel ''[[Monsieur Lecoq]]'', published in 1868, [[Monsieur Lecoq]] finds that a prisoner is communicating with his confederate using a double book cipher.{{clarify|date=February 2021 |reason= What is a double book cipher?}} Since the prisoner has only one book, ''The songs of [[Pierre-Jean de Béranger|Béranger]]'', the solution is easily discovered.
* In ''[[The Valley of Fear]]'', [[Sherlock Holmes]] decrypts a message enciphered with a book cipher by deducing which book had been used as a key text.
* The name of [[Ken Follett]]'s World War II thriller ''[[The Key to Rebecca]]'' refers to a [[Abwehr|German spy]] in [[Cairo]] using [[Daphne du Maurier]]'s novel ''[[Rebecca (novel)|Rebecca]]'' as the basis of a code.<!--why he wasn't provided an actual code prepared by ''Abwehr'' or ''B-Dienst'' is never explained...-->
* In ''[[A Presumption of Death]]'', [[Lord Peter Wimsey]], on assignment for British Intelligence in World War II Nazi-occupied Europe, uses a code based on the works of [[John Donne]]. The Germans break the code, coming near to catching Wimsey and Bunter. Wimsey then improvises a new code, based on an unpublished text known only to himself and his wife.
* [[Graham Greene]]'s protagonists often use book codes. In ''[[The Human Factor (novel)|The Human Factor]]'', several books are used, and an edition of [[Charles Lamb (writer)|Charles Lamb]]'s ''[[Tales from Shakespeare]]'' is used in ''[[Our Man in Havana]]''.
* A book cipher plays an important role in the TV version of ''[[Sharpe's Sword (TV programme)|Sharpe's Sword]]''. The key text is Voltaire's ''[[Candide]]''.
* In the 2004 film ''[[National Treasure (film)|National Treasure]]'', a book cipher (called an "Ottendorf cipher") is discovered on the back of the [[United States Declaration of Independence|U.S. Declaration of Independence]], using the "[[Silence Dogood]]" letters as the key text.
* The protagonists of the [[Matthew Reilly]] novel ''[[The Six Sacred Stones]]'' used a book cipher to send confidential messages to each other.  The key text was the [[Harry Potter]] books, but the messages were sent ''via'' a ''[[The Lord of the Rings]]'' forum to make the key text harder to identify.
* In ''[[Lost (2004 TV series)|Lost]]: Mystery of the Island'', a series of four [[jigsaw puzzle]]s released in 2007, a book cipher was used on each puzzle's box to hide spoilers and reveal information about the show to the fans.
* "The Fisher King", a two-part episode of ''[[Criminal Minds]]'', features a book cipher brought to the [[Behavioral Analysis Unit]] by the UNSUB via Agent Hotchner's wife. The cypher was part of a larger puzzle to find a girl who had been missing for two years. The key text was ''[[The Collector]]'' by [[John Fowles]].
* ''[[Burn Notice]]'' (episodes "Where There's Smoke" and  "Center of the Storm", 2010):  Michael Westen steals a Bible from a safe deposit box that is the code book of Simon. This becomes part of the season plot to track an organization starting wars for profit as Michael tries to arrange an interview with Simon.<!--unexplained is why Westen doesn't simply break the damn cypher.-->
*In the episode "[[The Blind Banker]]" of the BBC series ''[[Sherlock (TV series)|Sherlock]]'', [[Sherlock Holmes]] searches for a book that is the key to a cipher being used by [[Tong (organization)|Chinese Tong]] smugglers to communicate with their agents and with each other through graffiti messages. He eventually finds it: the  [[Geographers' A–Z Street Atlas|London A-Z]].
* In the film ''[[Unknown (2011 film)|Unknown]]'' (2011), Prof. Bressler's passwords are obscured by a book cipher.
* In ''[[The Unit]]'' episode "[[Paradise Lost (The Unit)|Paradise Lost]]", Jonas Blane (a.k.a. Snake Doctor) uses a book code from the poem ''[[Paradise Lost]]'' to communicate to his wife, [[Molly Blane|Molly]], that he has arrived safely in Panama.
* In ''[[The Good Soldier Švejk]]'' by [[Jaroslav Hašek]], the officers in Švejk's [[battalion]] attempt to use a book cipher. Their attempts are undone, however, when it is revealed that the novel in question is composed of two volumes, and Švejk has delivered the first volume to the officers, thinking that they intended to read the novel, rather than the second, which is used for the cipher. Furthermore, the key to the cipher is identical to an example given in a published military textbook.
* In ''[[An Instance of the Fingerpost]]'', a [[historical fiction|historical mystery]] by [[Iain Pears]], a book cipher conceals one character's family history and its relationship with the [[English Civil War]].
* In John Le Carre's ''[[A Perfect Spy]]'', the protagonist Magnus Pym uses a book cipher based on the German text Simplicissimus.
* In the book ''[[Red Dragon (novel)|Red Dragon]]'', [[Hannibal Lecter]] uses a book code to encrypt a message to the [[Francis Dolarhyde|Tooth Fairy]] killer, with the message containing the home address of [[Will Graham (character)|Will Graham]], who is investigating the case, and the message, "Save yourself. Kill them all", with the intent of having Will and his family fall victim to the killer. In the 1986 film adaptation [[Manhunter (film)|Manhunter]], the book used is mentioned to be a list of statues in the state of [[Maryland]]. In the 2002 adaptation [[Red Dragon (2002 film)|Red Dragon]], the book is changed to the French cooking encyclopedia [[Larousse Gastronomique]] to fit in with that movie's depiction of Lecter.
* In ''The Darwin Code'' by J D Welch, Jess uses a Shakespearean speech to construct a book cipher to communicate with an enemy who may or may not be an ally.
*In Bitterblue by Kristin Cashore, Bitterblue uses a book(?) code to unlock secrets of her father's reign as king.
*In the TV series ''[[Deutschland 83]]'', protagonist Martin Rauch's [[East German]] handlers use a book cipher to communicate with him while he is undercover in [[West Germany]].
*In the series 2 finale of the BBC TV show ''[[Luther (TV series)|Luther]]'', two brothers use a book cipher. Luther determines they must be using a book that is readily available in case the book is lost and/or so the users can always have it to hand. This leads him to discovering the book cipher is using Gideon's Bible.