Fictional Document

"Kryten: Sir, the Space Corps Directives are there to protect us. They are not a set of vindictive pronouncements directed against any one person.

Rimmer: Has anyone ever seen this legendary Space Corps Directive Manual?

Lister: Well... no.

Rimmer: He's making it up, isn't he? The bloody book doesn't exist!"

- Red Dwarf, "Quarantine"

All the books, magazines, and newspapers that exist only within a fictional world, from the Necronomicon to the mysteries of Jessica Fletcher. They are more common in Speculative Fiction, but not restricted to it.

They serve two main narrative purposes: verisimilitude and Exposition. Jessica is supposed to be an author; it would be bizarre if no trace of the books she writes existed. Reading the Necronomicon may frighten the protagonist half to death, but it also gives the reader an idea of the Backstory.

Fictional documents are also used to comment on literary tropes, and as aids to characterisation. Characters comparing their own predicament with their favourite book can get very sarcastic about how unrealistic it was, while few things so embarrass the Action Girl as having her little brother read aloud a few choice passages from her favourite romance. Sometimes, however, you may just have to Take Our Word for It.

Common types of fictional document include:


 * Apocalyptic Log
 * Big Book of War
 * Encyclopedia Exposita
 * Great Big Book of Everything
 * In-Game Novel
 * Recursive Canon
 * Tome of Eldritch Lore

If your story is made entirely of Fictional Documents, it's a Scrapbook Story (so please list it there rather than here); if the Paratext quotes from these, it's quoting the Encyclopedia Exposita. And if the story itself appears in the story, it's Recursive Canon. If it merely claims to have been written by a character within the setting, it probably falls under the Literary Agent Hypothesis. In a Video Games, they are almost always use as Flavor Text.

Occasionally prone to Defictionalization.

Anime and Manga

 * Much of Princess Tutu's plot revolves around the fictional fairytale The Prince and the Raven.
 * Near the end of the Chrono Crusade manga, there's quotations from both Mary Magdalene's prophecies, and Azmaria's memoir. It's implied that at least some of the manga is "based on" the book Azmaria wrote.
 * D.N.Angel has a plotline focused around the fictional fairytale Ice and Snow--which turns out to be the edited, abridged version of the original tale, Ice and Dark.
 * The villain of Monster bases his identity on a brainwashing children's book. The story, along with several others, is reproduced in the series with full text and illustrations.
 * Chobits features a picture book which corresponds to the main character so completely that is becomes of little wonder when it's revealed that
 * A major chunk of the plot of Whisper of the Heart revolves around the main character struggling to write her first novel - which was later Defictionalized.

Comic Books
"Chapter 1, 2 and 3: Chapters 1 through 5 of Under the Hood, written by Hollis Mason (Nite Owl I), discussing the story of the earlier crimefighters.
 * Under the Hood, Hollis Mason's autobiography, and a Tales From the Black Freighter comic in Watchmen.
 * Also parts of Dr. Manhattan's back story.
 * Hell, pretty much all of the 11 backup features in Watchmen count:

Chapter 4: Dr. Manhattan: Super-Powers and the Superpowers by Dr. Milton Glass, discussing Manhattan's role in shaping the world of Watchmen.

Chapter 5: A Man on Fifteen Dead Man's Chests, a history on Tales From the Black Freighter from Treasure Island Treasury of Comics.

Chapter 6: A variety of documents chronicling Rorschach's personal history, sources including the New York Police Department, the Charlton Home and the New York State Psychiatric Hospital.

Chapter 7: Blood From the Shoulder of Pallas, an essay written by Dan Dreiberg (Nite Owl II)

Chapter 8: The New Frontiersman Issue IVII No. 21, discussing the vigilantes from a Right-Wing perspective.

Chapter 9: A variety of news clippings chronicling Sally Jupiter's career.

Chapter 10: Various memos from the desk of Adrian Veidt.

Chapter 11: After the Masquerade: Superstyle and the art of humanoid watching, an interview with Adrian Veidt from 1975."


 * Similar to the Watchmen example, there's also Alan Moore's The League of Extraordinary Gentlemen: Black Dossier, in which the titular Black Dossier is a Fictional Document, containing excerpts from other Fictional Documents: Oliver Haddo (of The Magician)'s "On the Descent of the Gods"; British comic strip Trump's "Life of Orlando"; a lost Shakespeare play entitled Faerie's Fortunes Founded; a sequel to Fanny Hill; a Jeeves and Wooster story detailing an encounter with a Great Old One; and a novel, The Crazy Wide Forever, by Kerouac's alter ego Sal Paradyse, as well as a pornsec booklet as produced by the Minitrue of Nineteen Eighty-Four. Earlier volumes also included an Allan Quatermain short story, a traveler's almanac, and various fictional Victorian advertisements, posters, postcards, &c. as All There in the Manual-type extra features.
 * In The Sandman, Dream's castle includes a library of books that were never written.
 * The DC Universe features "true crime" comics of Superman, Batman, Wonder Woman, etc.'s adventures, presumably taken from media accounts, etc.; one late 60s Batman story made use of this as its plot (Batman forced to confront the writer of his world's "Batman" comic).
 * Superman of course features the great metropolitan newspaper The Daily Planet.
 * As does Lois Lane, who also had a novel published.
 * Captain Carrot and His Amazing Zoo Crew features fictional Earth-C versions of some DC Comics characters. Captain Carrot in his alter ego works as a writer/artist for his world's DC Comics, writing stories about "Super-Squirrel", "Wonder Wabbit", "the Batmouse", and the "Just'a Lotta Animals" (though the Zoo Crew later discovered that their "fictional" comics characters were actually real, on the parallel world of Earth-C-Minus).
 * Marvel examples:
 * The New York-based daily newspaper, The Daily Bugle. J. Jonah Jameson also used to publish Now and Woman magazine. The latter was edited for a time by Carol Danvers aka Ms. Marvel.
 * The Darkhold, which among other things contains the Montesi Formula, which destroys vampires.
 * Dr. Strange's friend Morgana Blessing has published books about the occult.
 * Destiny's diaries, which contain(ed) many visions of the future.
 * Pyro, her teammate in the Brotherhood/Freedom Force is a best-selling novelist.
 * Marvel Comics, which in the Marvel Universe for the most part are licensed by the heroes depicted in them. For a time, Steve Rogers was put in charge of drawing the Captain America comicbook.
 * Peter Parker put out Webs, a coffee-table book of photographs of Spider-Man.
 * In Empowered mention is made of a lot of slash fan-fiction especially involving the male Superhomeys. Some of the latter was written by Emp herself using a pseudonym.
 * The Junior Woodchucks' Guidebook, the most stupendous and comprehensive guide to everything.
 * The tourist guide Syldavia, Land of the Black Pelican, a few pages of which are reprinted in King Ottokar's Sceptre. And by extension the 14th and 15th-century manuscripts from which some of its illustrations were taken.
 * The manuscript "Journal of Sir Francis Haddocke, Captain in the King's Navy, Commander of the vessel Vnicorn" from The Secret of the Unicorn.

Fanfiction

 * Kyon Big Damn Hero opens every chapter with an excerpt from one of these, whether a guide to being a hero, poetry, or some sort of diary.
 * The Exoria Files.
 * In the Fullmetal Alchemist fan fiction "The Game of Three Generals," after it's announced that his wife is pregnant, Roy Mustang is gifted with an expectant father's advice book called Look What You Did to Me.

Film

 * Mirror Mask has "The Really Useful Book" and "A Complete History of Everything"
 * In the original novel Frankenstein, the actual method of bringing the Monster back to life is never detailed. In the Mel Brooks film Young Frankenstein, this fact is parodied by the discovery of a book by Frankenstein entitled simply How I Did It.
 * This is sort of Hilarious in Hindsight today after O.J. Simpson wrote a similarly titled book about how he murdered his wife (hypothetically, of course).
 * How could anyone forget the great Depression Era novel O Brother Where Art Thou by Sinclair Beckstein, as cited by director John Sullivan in the 1941 Sullivan'sTravels?
 * No real details about the book are ever given, but the Coen brother's 2000 film of the same name fits the supposed saga nicely in plot and details.
 * In Finding Forrester, Sean Connery's eponymous character's reputation is entirely based on his only novel, Flying to Avalon.

Literature

 * When medieval poet Wolfram von Eschenbach wrote Parzival, a German retelling and continuation of Chretien De Troyes' Perceval, he answered criticism of discrepancies between his version and Chrétien's earlier ones by claiming he was being faithful to the original account by one "Kyot the Provencal", whom he alleged to have been Chrétien's source as well.
 * JRR Tolkien's Middle-earth legendarium (The Lord of the Rings, etc) has lots of fictional pieces of literature, both in prose and poetry, and also historic and scientific texts. Most well known is for obvious reasons the Red Book of Westmarch, which contains Bilbo and Frodo's The Downfall of the Lord of the Rings and the Return of the King.
 * The Book of Mazarbul, the record of Balin's doomed Moria colony in The Lord of the Rings
 * The Encylopedia Galactica, Isaac Asimov's Foundation series.
 * The Grasshopper Lies Heavy, P. K. Dick's The Man in the High Castle
 * The Hitchhikers Guide to The Galaxy
 * Stephen King occasionally has characters in one book reading a book written by a writer who was a character in another book, such as Rose (Rose Madder) reading Paul Sheldon (Misery), or Jo (Bag of Bones) reading William Denbrough (IT), or Darla (Lisey's Story) listening to an audio book by Michael Noonan (Bag of Bones) or Fran (The Stand) reads a book by Bobbi Anderson (Tommyknockers) to someone. In The Tommyknockers, Bobbi's neighbors compare her favorably to "that other writer" from Maine, who writes the stories with all the monsters and cursing (King himself).
 * Speaking of Stephen King, a large percentage of Carrie is excerpts from books, magazine articles, or investigative reports relating to various characters and events.
 * King does it again in The Regulators (under pen name Richard Bachman), interspersing narrative with newspaper clippings, letters, diary excerpts, etc.
 * The Theory and Practice of Oligarchical Collectivism, George Orwell's Nineteen Eighty-Four.
 * Jorge Luis Borges LOVED this trope. The biggest example is the collection of short stories called El jardín de senderos que se bifurcan, where all the stories were are fictional books.
 * David Eddings loves these. The prologues of nearly all his books take the form of a fictional document detailing what has gone on before.
 * Some that specifically deserve to be called out from The Belgariad: The Mrin Codex and the Darine Codex are the collected ravings of two madmen inspired by the prophesy of light. The Ashabine Oracles are writings by Torak under the influence of the prophecy of dark.
 * Juliet McKenna likes them even more; she prefaces nearly every chapter with a fictional document. Some of them are only tangentially relevant.
 * The Princess Bride is a real novel written as if it were the annotated 'just the good bits' version of an even longer novel about the history and culture of the fictional nation Florin.
 * In Der Schimmelreiter (The Rider on the White Horse) by the 19th-century German writer Theodor Storm, the narrator claims to be piecing together from memory a novella he read as a youngster.
 * Craig Thomas has used this at least twice in his novels, such as Wolfsbane and Firefox.
 * The Book of Night With Moon from Diane Duane's Young Wizards series.
 * The excerpts from Princess Irulan's various scholarly works (and other people's, for that matter) that appear as chapter headers throughout the Dune novels.
 * There's also The Orange Catholic Bible that Yueh gives Paul.
 * Mr. Bunnsy has an Adventure, a Beatrix Potter pastiche from Terry Pratchett's The Amazing Maurice and His Educated Rodents
 * Pratchett is very fond of this trope; other examples from Discworld include The Necrotelicomnicon aka Liber Paginarum Fulvarum (a Tome of Eldritch Lore), The Joy of Tantric Sex with Illustrations for the Advanced Student, by A. Lady, The Book of Going Forth Around Elevenish, The Little Folks' Book of Flower Fairies, The Bumper Fun Grimoire, How to Dynamically Manage People for Dynamic Results in a Caring Empowering Way in Quite a Short Time Dynamically, Wellcome to Ankh-Morporke, Citie of One Thousand Surprises, and many more, usually parodic versions of real books. The Discworld Companion includes a full list.
 * Several have been Defictionalised for merchandising purposes, including Where's My Cow? (a children's book) and Nanny Ogg's Cookbook (a follow-up to her in-universe book The Joye of Snackes).
 * Some of the books even become important plot devices, like The Summoning of Dragons (slightly foxed and heavily dragoned), What I Did on My Holidays, and the first newspaper in Ankh-Morpork.
 * Good Omens: The Nice and Accurate Prophecies of Agnes Nutter, Witch contained both The Nice and Accurate Prophecies of Agnes Nutter, Witch (obviously) and
 * About half of each the books in The Pendragon Adventure is journals from Bobby Pendragon himself, detailing his stays and attempts to save the Territories.
 * Extracts from Thursday Next's autobiography are scattered throughout the series of the same name. Extracts from others characters' jottings/memoirs also feature prominently.
 * In Ayn Rand's Atlas Shrugged, one of the so-called intelligentsia writes an article titled "The Octopus" which slams Henry Rearden. Then there's "Why Do You Think You Think?", "The Heart is a Milkman", "The Vulture is Molting", and even a "The Future" magazine. Then there's the laws and regulations and plans, including the "Anti-Dog Eat Dog Rule" to the "Equalization of Opportunity" bill to the "Railroad Unification Plan" to the "Steel Unification Plan". There are even audio versions, with Richard Halley's works and its bastardizations.
 * The novels and short stories of Kilgore Trout, a failed science fiction author who's a recurring character in several of Kurt Vonnegut's novels. His 117 novels and 2000 short stories were published by a disreputable porn company and used as filler material for trashy erotic magazines though, so only a handful of other characters have ever heard of Kilgore Trout. His novel Venus On The Half Shell ended up making the transition from fictional document to real book when sf writer Philip José Farmer wrote and published it under the name Kilgore Trout (Vonnegut was apparently not amused, and the byline in later editions was Farmer's own name).
 * Harry Potter has stacks of these, from trading cards to school textbooks to government pamphlets to wizarding comic books.
 * Not to mention JKR's predilection for turning some of them into published works (Fantastic Beasts and Where To Find Them, Quidditch Through the Ages, The Tales of Beedle the Bard).
 * Speculative Fiction author Bruce Sterling's short story Our Neural Chernobyl was written as a review of a fictional monograph (a non-fiction book on a specific real-world topic) about the "neural Chernobyl," which described the development, release, and consequences of a retrovirus that caused massive growth in brain complexity in almost all mammals, something catastrophic for humans as the process makes humans massively intelligent, but effectively burns out the brain after a while. The story even touches on the book's exploration of the controversial topic of non-human uplifting from the virus, where many animals became much more intelligent, to the point cats developed torture devices to use on mice.
 * The King in Yellow, a fictional play script from the book of short stories of the same name.
 * The version written by Thom Ryng is actually quite good, though it fails to drive its readers or players insane.
 * Used extensively in Jack Vance's The Demon Princes series. A lot of the chapters, in fact, start with more or less related quotes from various invented works. Titles mentioned include the many-volumed "Life" by Baron Bodissey or the "Scroll from the Ninth Dimension". Also quite prominent in the story is a fictional magazine named "Cosmopolis".
 * In particular, the film The Navidson Record from House of Leaves doesn't actually exist, and the protagonist tells you this in the book's introduction. Meanwhile, the meat of House Of Leaves is an academic analysis/summary of said film. A few of the people and books referred to in the analysis's footnotes are real; the vast, vast majority of them are completely made up.
 * The French sci-fi writer Bernard Werber frequently uses this device. The Ants trilogy has fragments from his fictional character Edmond Wells's Encyclopedia of Relative and Absolute Knowledge, which was later published in paperback form under Werber's name (rather disappointingly, it mostly intersperse the bits already quoted from it and include little, if any new material). This last detail is egregious since Wells explains in his atypical encyclopedia that he thinks he is turning schizophrenic and the paperback makes it sound as if it were Werber's voice (moreover, Edmond actually dies just before the beginning of the first novel and only appears through flashbacks and the Encyclopedia, and he's a bit of a Mad Scientist at that). Also, the Thanatonautes series has fragments from a character's collection of world myths and legends concerning life after death. Yes, you know what it means.
 * Everything published by Whateley Press in the Whateley Universe, including "Introduction to the Modern Theory of Mutant Powers, a Whateley Press textbook" by Filbert R. Z. Quintain, M.S., Ph.D., F.A.A.S.
 * Used from time to time in Sword of Truth, mostly in the form of books of prophecy. Being prophesies, they are then promptly ignored.
 * The Books of Pellinor are all written as if they are histories of the fictional land the books are based in. The back of the book even includes annotations, a bibliography, family trees and various other fictitious documents.
 * The Book of Ultimate Truths is about a search for the missing chapters of a book called The Book of Ultimate Truths, a book about the secrets of the world.
 * The Bookof All Hours in Hal Duncan's duology of the same name.
 * And of course the aforementioned Necronomicon, spawned in the Lovecraft horrorverse but since widely exported to other canons and other media.
 * Now subverted as an actual Necronomicon has been published.
 * In fact, many different Necronomicons have been published over the years. Their quality... varies. Some are merely collections of Mythos stories. Others run the gamut from psudeophilosophical ramblings to attempts at a "genuine" version of the Mad Arab's writings.
 * The Other Wiki has a rather extensive list of Cthulhu Mythos arcane literature, most of which falls under this trope. The Book of Eibon, Unaussprechlichen Kulten, and De Vermis Mysteriis are mentioned nearly as often as The Necronomicon.
 * Much of Karel Čapek's War With the Newts consists of fictional newspaper excerpts commenting on the situation with the Newts (and, eventually, the eponymous war).
 * This trope appears as a central theme in the book The Diamond Age by Neal Stephenson. In it, the protagonist girl is given a very high tech teaching book by the name of "The Young Ladies' Illustrated Primer," which also appears as a subtitle of the book.
 * It's not so much a fictional document as a fictional nanotechnological superweapon, but most of the time it looks and acts like a book.
 * Several of the Warhammer 40000: Horus Heresy books have characters talk about an epic called The Chronicles of Ursh. They never go into more detail about it.
 * In the Ciaphas Cain novels, Amberley Vail uses extracts from other sources to fill in the blanks left by Cain's self-centered account. These include the Purple Prose-filled memoirs of a future general in his unit, histories of varying accuracy, travel guides, and even a children's book about promethium.
 * Sex Is My Adventure, Josella Playton's undeservedly-infamous novel in The Day of the Triffids.
 * Italo Calvino's If on a winter's night a traveler has excerpts from ten wildly different fictional novels, though the Reader can never get past the first chapter of each.
 * The Others from the Night Watch series have effected The Great Treaty between Light and Darkness (hereinafter referred to as The Treaty) that restricted the century-old bloodshed between the Light Ones and the Dark Ones, regularized the relations between the two factions and stipulated formation and functioning of the Watches.
 * Garth Nix's Keys to The Kingdom has The Compleat Atlas, which is a magic book that will tell you anything about the House.
 * Many of the page quotes in Dean Koontz novels are from The Book of Counted Sorrows, though this eventually became The Red Stapler.
 * "Being a Reprint from the Reminiscences of John H. Watson, M.D. , Late of the Army Medical Department"
 * Also Sherlock Holmes' treatise on the different types of cigare(ette) ash.
 * The book The Hive Queen and the Hegemon is one of the most influential in the society of the Ender's Game Series.
 * Inkheart is the most important plot device within its eponymous frame story.
 * Most of the books on the pig-related shelf in the library of Blandings Castle, including most notably Lord Emsworth's favourite, Whiffles On the Care of the Pig. (The title is given with variations in different novels, in Galahad at Blandings the author is called Augustus Whipple).
 * Other PG Wodehouse examples: the inter-class romance novels of Rosie M. Banks (examples include A Red, Red Summer Rose, Only a Factory Girl, The Woman Who Braved All, The Courtship of Lord Strathmorlick, Madcap Myrtle, and Mervyn Keen, Clubman) and various detective novels read by the protagonists (which generally have overblown titles like A Trail of Blood).
 * In the Star Trek Voyager Relaunch, the Royal Protocol document, bane of Starfleet Officers everywhere. A complete list of dos and don'ts for interacting with alien royals, it's a necessity if diplomatic incidents are to be avoided. It's mind-numbing in its detail, full of little rules along the lines of "when greeting the King, touch your head to the ground three times and then wave your left hand. Oh, and under no circumstances wear purple". An important plot point arises when it's realized "Royal Protocol" has a very different meaning to the Borg.
 * The Fault in Our Stars features An Imperial Affliction as well as The Price of Dawn and the following sequels.
 * The epigraph of The Fault in Our Stars is from An Imperial Afflicton, as a reference to The Great Gatsby, whose epigraph is also from another fictional book.

Live Action TV

 * Bones makes frequent reference to the novels that Brennan has written, and one episode includes a series of murders that imitate those in one of her books. (In a playfully meta note, the books have the same title scheme as the Kathy Reichs novels that the series is based on, and "Kathy Reichs" is the name of Brennan's fictional forensic anthropologist.)
 * Blush, the fashion magazine whose offices are the setting for Just Shoot Me.
 * The Chronicle, the tabloid from the short-lived show of the same name.
 * The fat sci-fi paperback Stephen Colbert's Alpha Squad 7: Lady Nocturne: A Tek Jansen Adventure is, inexplicably, not popular with publishers. Colbert eventually decided to self-publish in the form of comic books and animated shorts, both of which do exist in Real Life.
 * Agent McGee's novels in NCIS. In one episode, characters from his book are being killed--a book that hasn't even been published.
 * Jake Sisko's novel Absalam in Star Trek Deep Space Nine. Particularly important to the frame story of "The Visitor."
 * Also, the Ferengi "Rules of Acquisition", which is considered to be the most important book in the entire Ferengi culture.
 * Criminal Minds has several:
 * David Rossi is the author of several books on criminal psychology; an UnSub quotes from them in an interrogation scene in "Masterpiece."
 * A new book on the Keystone Killer induces the unsub to resume his murderous ways in "Unfinished Business."
 * A reporter who wrote a book on the Boston Reaper is a character in "Omnivore."
 * Professor Ursula Kent's SF novel in "Empty Planet."
 * Johnny McHale's comic book Blue in "True Night."
 * Shortly after the above quote from Red Dwarf, Holly beams a hologramattic copy of the Space Corp Directives into Rimmer's hands, proving they exist. It's much thinner than you might think. The rules are apparently in small type.
 * In an episode of Corner Gas, at the end Brent does an "if you want to find out more, visit your local Library!" segment with the books featured in the episode. One of them he mentions is something "the prop guy made up" but is "a good read".
 * The Bro Code, which Barney quotes on various occasions in one episode of How I Met Your Mother. Barney claims it was written by his ancestor Barnabas Stinson on the back of the U.S. Constitution. It is heavily implied that Barney just made it all up, making this a fictional fictional document.
 * Subverted now since the Bro Code is now an official book.
 * Richard Castle's MANY novels in Castle.
 * Well, the Derek Storm novels at least. Heat Wave is being Defictionalized.
 * On Lost, Sawyer reads a fictional manuscript for a novel called "Bad Twin" that was later Defictionalized.
 * Between season 5 and 6, a fictional documentary TV episode on the DHARMA Initiative has been released.
 * The horror novels of Garth Marenghi. Garth reads out passages at the start of episodes and has Dagless read one of them to keep his mind occupied.

Print Media

 * Calvin and Hobbes has Hamster Huey and the Gooey Kablooey, as well as Chewing, a magazine about chewing gum. (Also, Commander Coriander Salamander And 'Er Singlehander Bellyander, the sequel to Hamster Huey is mentioned once.)
 * Peanuts made reference to a whole series of books starring The Six Bunny-Wunnies on various adventures, authored by one Helen Sweetstory. Over a dozen titles were given, each usually mentioned only once, but The Six Bunny-Wunnies Freak Out is the most widely remembered for having been banned by the local school board and subsequently championed by Linus.

Tabletop Games

 * Magic the Gathering has numerous fictional documents that are quoted in cards' flavor text and in some of the novels and comics. Some of the notable ones include The Antiquities War, an epic poem about the Brothers' War that the comics and novel are supposedly based on; Sarpadian Empires, whose first six volumes are quoted in Fallen Empires flavor text and whose seventh volume was printed as a card in Time Spiral; and The Underworld Cookbook, which is only quoted on three cards (one of which is from the self-parody expansion Unhinged), but whose author's name, Asmoranomardicadaistinaculdacar, is the longest word ever to appear on a Magic card. The Love Song of Night and Day actually exists and was written as part of the worldbuilding for the Mirage expansion, and can be read here.
 * The end of the latest block, Rise Of The Eldrazi, had quotes from a book called the War Diaries as flavour for some cards. It seems like an account of the terrible fighting against the Cthulu-sytle horrors of the Eldrazi, and contains sentences about crucical turning points.
 * A pair of meta-examples from Dungeons and Dragons: The Book Of Exalted Deeds and the Book Of Vile Darkness, which exist as powerful artifacts in-universe and useful splatbooks out-of-universe.
 * Forgotten Realms uses it via its Literary Agent Hypothesis: at least Aurora's Whole Realms Catalogue and every Volo's Guide to [blank] are supposed to be "actual" books printed on Toril, and some others, like Elminster's Ecologies mostly consists of various in-'verse Exposition texts.
 * The Ravenloft campaign setting features the Tome of Strahd, an exceedingly rare manifesto written by Strahd von Zarovich which serves as the foreword of the Ravenloft sourcebook. Also, and more popularly, there are the Van Richten's Guides, written by famed doctor and monster hunter Ruldolph van Richten. Copies of these books are published and distributed by the doctor's office and serve as guides on proper hunting techniques. Often, Dr. van Richten complains in his books that there are so many other inferior and incorrect works on monster hunting in existence that he sees it as his duty to put out properly researched guides that won't get novice hunters killed. Out of universe, the Guides exist and are written in the author's voice for the fluff sections, though it is assumed that any crunchy statistics and in-game information is ghosted out of the in-universe versions.
 * Much of the rich background information for Warhammer 40000 is conveyed through quotes, after-action reports, or excerpts from fictional investigations, histories, or journals. In an example of Defictionalization, one such book, The Imperial Infantryman's Uplifting Primer, has actually been published.
 * Exalted has a lot of these, some of which have been Defictionalized. Notable examples include The Broken-Winged Crane, The Thousand Correct Actions of the Upright Soldier, The Book of Three Circles, The White Treatise, The Black Treatise, The Book of Bone and Ebony, and Oadenol's Codex.
 * White Wolf enjoys making these - they did three for Vampire: The Masquerade (The Book of Nod, The Prince's Primer and Revelations of the Dark Mother) and another for Werewolf: The Apocalypse (Chronicles of the Black Labyrinth).

Video Game
"Double H: CAARRRLSONNN AAAND PEEETERRRRS! -Whack!-"
 * Several games have used fictional documents as part of the documentation. Well-known examples include text adventures from Infocom and Ultima series.
 * Metal Gear Solid has a few books mentioned in the game. Most notably one called "In the Darkness of Shadow Moses", a novelization of the events of the first game which is available to read on the main menu of MGS2.
 * Any number of texts found within The Elder Scrolls games, ranging from popular histories such as The Real Barenziah and A Brief History of the Empire, through religious texts such as For My Gods and Emperor and 36 Lessons of Vivec, to novels such as A Dance in Fire and The Wolf Queen. Many of the histories presented within the game are contradictory and at odds with each other, leaving it up to the reader to piece together the history of Tamriel for him/herself.
 * The best is Morrowind's The Lusty Argonian Maid. It's... umm... a play. A side-quest involves finding actors willing to be in it.
 * And Boethiah's Pillow book is unmentionable.
 * There is a good laugh in The Madness of Pelagius, after having read The Wolf Queen vol. 8, which describes an amulet given to Pelagius that robs the wearer of sanity over the course of years.
 * Also from Bethesda, the Wasteland Survival Guide in Fallout 3, the quality of which depends on how much work you put into it, including none at all!
 * Monkey Island 2 has an entire library of fictional documents, mostly comprised of various jokes, in-jokes, and parodies.
 * The Emigre Document of Shadow Hearts, seemingly based on the untranslatable Voynich Manuscript carries in it all manner of dangerous knowlege including resurrection. That part always fails in the most catastrophic ways possible, usually summoning soulless abominations from your loved ones corpse to devour them and you as well.
 * If that is not Lovecraftian enough, also available is the R'lyeh Text, translated as Codex of Lurie, which I believe you find in a nudie mag.
 * In the vein of plot-important fake books is In-Laqetti, of Persona2 fame. A composition of patchwork conspiracy including aliens, Mayans, and Master-D himself, which would apparently cause the world to go bye-de-bye. Thanks to a bit of kotodama and extreme Wikiality, things start coming true.
 * The hugely popular novel (and later play) LOVELESS is frequently quoted by Genesis in Final Fantasy VII Crisis Core, It's apparently very moving, but we never find out what the novel is actually about.
 * Baldurs Gate is full of these. Some provide plot-relevant information ("The History of the Dead Three") other just notes on the setting. One is a recipe for cookies.
 * Its Dragon Age spiritual successors are full of fictional documents - books with notes on the setting, silly poetry, letters between characters, and Varric's schlocky novels (Hawke: "'Hard in Hightown.' 'Siege Harder.' What does that even MEAN? Ohh, Varric must be stopped.") Particularly prevalent is Anders's Manifesto, which the rebel mage appears to have stuffed in every book on Hawke's shelf, left on every table, and dropped in the fireplace. (Some fans have even attempted a Defictionalization of it.)
 * In Beyond Good and Evil, Jade's sidekick Double H quotes passages frequently from the the 'Carlson & Peeters' military manual, a Big Book of War. While the player eventually does see a section of the book in digital form, most of what we know about the book is from Double H offering advice from the book as quoted passages: "If you can't go through a door, go around it!". Perhaps one of the few fictional documents which also serves as inspiration for someone's Battle Cry.


 * The Books of Chzo, which includes The Book of The Bridge, the Book of The New Prince, The Book of Victims, and the Book of The Prince. These Books are shown in pieces throughout the Chzo Mythos in order to flesh out most of the back-story and themes of the series.

Web Comics
The author even parodies his use of this trope, by having Unwinder write his own webcomic, with said webcomic featuring its own, uniquely dull, fictional novel: The Gun and the Grapes, which cranks Narrative Filigree up to eleven. Back in the main comic, a reader is unimpressed by Unwinder's metafiction. "Amy: I can't really tell what you're going for here. ... You invented an intentionally boring author and provided an intentionally boring prose sample. Mission accomplished. Now why should I care?
 * Gunnerkrigg Court: While researching the minotaur, Antimony was unimpressed with Gainsbury World Mythology and Mythology 4 Kidz! as sources. Later, she's seen reading Tannhauser Gate, and Kat borrows Important Stuff (Like Science) from the library.
 * In part 2 of the Lebanese comic Malaak: Angel of Peace, a collage of fictional newspapers is used on one page to suggest that the heroine has piled up missions and has been noticed by the general public. The papers' titles and contents (ads included) are all parodies of actual papers and places.
 * The various popular Heterodyne Boys pulp novels in Girl Genius.
 * And less popular, the Trelawney Thorpe: Spark of the Realm books, which are from British publishers.
 * The various mad science journals (including the New Journal of Malology) from Narbonic.
 * In The Life of Nob T Mouse and All Over the House, The Blobland Gang is a set of books, TV & radio shows, and even a film. They are all based on Hubert Schlongson's visits to Blobland to learn about the adventures of Nob Mouse and Company.
 * The Way of the Metagamer's sequel, The Way Of The Metagamer 2: In Name Only, exists only within the comic.
 * The Seventy Maxims of Maximally Effective Mercenaries of Schlock Mercenary.
 * Unwinders Tall Comics are loaded with fictional books. Unwinder is a fan of the After Dark series, a romance novels involving zombies who are actually super-attractive athletes who can also fly, as well as the epically dull sci-fi doorstoppers of Gary P. Rastov. Excerpts from all of these are provided, of course.

Unwinder: There's... there's a certain audience for this."


 * Several are mentioned in passing in The Mansion of E.

Web Original

 * The entry on the Iormunean Imperium in Open Blue's Worldbook quotes multiple fictional documents as the source of information for the otherwise completely unknown lost civilization.
 * The Worldbook's article on The Church also features verses from their holy book, the Book of Zod.
 * Port Allison's history also quotes passages from the island's discoverer, a Columbus expy named Julian Argenio.

Western Animation

 * One episode of Kim Possible features the "classic novella" Lo The Plow Shall Till The Soil Of Redemption. One critic describes it thusly: "snobby, pompous, overwritten, and the pictures [are] in black and white!"
 * A Futurama episode features the Becktionary and the Rhyming Becktionary.
 * The Simpsons has lots of these, including
 * Shall There Ever Be Another Rainbow?, C. Montgomery Burns' touching autobiography.
 * Bob Woodward's book about Jebediah Springfield.
 * Marge Simpson's bodice-ripper novel of Nantucket whaling.
 * Various stage works, most notably the musicals Streetcar! and Stop the Planet of the Apes.
 * Periodicals like The Springfield Shopper and Junior Sceptic Magazine.
 * Lisa's unfinished novel: They promised me ponies.
 * My Little Pony Friendship Is Magic:
 * The Just For Fun series.
 * An innumerable amount of reference works in Twilight Sparkle's library.
 * The Foal Free Press, the newspaper at the school the Cutie Mark Crusaders attend.
 * The Transformers follow the Covenant of Primus, a book of prophetic texts delivered by their creator-god, in many continuities, most notably Beast Wars and the "Aligned" continuity branch that includes the Transformers Prime TV series and a series of novels.