History GenreShift / Literature

* ''Literature/TheThirteenthWarrior'' begins as a translation/retelling of Ahmad ibn Fadlan's visit to the [[HornyVikings Volga Bulgars]]. Somewhere between the third and fourth chapters, however, it morphs into an ExternalRetcon {{Demythification}} of ''Literature/{{Beowulf}}''.

* ''Literature/AgentG'' by Creator/CTPhipps starts with the premise of being a James Bond-esque assassin in a ConspiracyThriller with science fiction elements before the entire world is devastated by a volcanic eruption and is transformed into a {{Cyberpunk}} {{Dystopia}}.

* ''Literature/AgentG'' by Creator/CTPhipps starts with the premise of being a James Bond-esque assassin with science fiction elements before the entire world is devastated by a volcanic eruption and is transformed into a {{Cyberpunk}} dystopia in the second book.

* ''Literature/TheBoyWhoCouldntSleepAndNeverHadTo'' turns from a coming-of-age tale to a frenzied escape from TheMan about 2/3 through.

* The Robert Langdon series, written by ''Creator/DanBrown'', is generally a thriller/espionage series, with a lot of historical fiction thrown in. The fourth in the series, ''[[Literature/DanBrownsInferno Inferno]]'' becomes full-on Sci-Fi with the revelation that the antagonist has [[spoiler: successfully sterilized one third of all humans on the planet]] by the end. Bizarrely enough, the succeeding novel ignores this development entirely.

* The Robert Langdon series, written by ''Creator/DanBrown'', is generally a thriller/espionage series, with a lot of historical fiction thrown in. The fourth in the series, ''[[Literature/DanBrownsInferno Inferno]]'' becomes full-on Sci-Fi with the revelation that the antagonist has [[spoiler: successfully sterilized one third of all humans on the planet]] by the end. Bizarrely enough, the proceeding novel ignores this development entirely.

* ''[[Literature/TheBoxcarChildren]]'' The first book is about some kids living on their own in a slice-of-life kind of story, without any mysteries. The sequels are all mysteries that the kids solve.

* [[Literature/TheBoxcarChildren]] The first book is about some kids living on their own in a slice-of-life kind of story, without any mysteries. The sequels are all mysteries that the kids solve.

* While ''Literature/WarriorsCats'' as a whole has always been a fantasy adventure series, the series' sixth arc, ''The Broken Code'', is a mashup between supernatural horror and a political thriller.

* ''Literature/TheDinosaurLords'' does a full ''Form'' Shift in the epilogue, turning from prose to drama - the final conversation is presented like a scene from a play.

* Happens fairly early on in ''Literature/TheLordOfTheRings''. The first chapter, and parts of the second, are very comical and whimsical, except for Gandalf's confrontation with Bilbo, whereas the rest is much more dark and grim. This has a lot to do with Tolkien trying to write a sequel to ''Literature/TheHobbit'' by [[ExecutiveMeddling editorial mandate]], but giving that up pretty early in favor of something connected to ''Literature/TheSilmarillion'' (which said Editor rejected). Even then, after the Fellowship splits, each character's story is, in many ways, a different genre, ranging from modern stories concerning war and morality to epic tales in a more medieval vein. These changes were more intentional than the shift out of a children's story, as Tolkien toyed a lot with the difference between medieval and modern works.

* ''Literature/RangersApprentice'' begins in classic fantasy style - a young orphaned hero has to fight against an evil sorcerer controlling an army of monsters. However, in later books there's not a shred of the fantastic to be seen; indeed, one story deals with an old man using primitive science to fake magic.

* The Robert Langdon series, written by ''Creator/DanBrown'', is generally a thriller/espionage series, with a lot of historical fiction thrown in. The fourth in the series, ''[[Literature/DanBrownsInferno Inferno]]'' becomes full-on Sci-Fi with the revelation that the antagonist has [[spoiler: successfully sterilized one third of all humans on the planet]] by the end. Bizarrely enough, the proceeding novel ignores this development entirely.
* Cecilia Dart-Thorton's ''The Crowthistle Chronicles'' starts off as a HighFantasy with some story elements taken from well-known fairy tales and myths and continues this way for 3 of its 4 books, but in Book 4 it's revealed that the [[AlienFairFolk FairFolk of the story are essentially aliens]] and much of the book becomes a PropagandaPiece against animal cruelty and meat consumption with much of the story elements of the previous books dropped.

* Creator/StephenKing's ''Mercedes Saga'' gradually shifts genre. The first entry, ''Literature/MrMercedes'', is a hard-boiled detective story with absolutely no paranormal or supernatural elements. The second book, ''Literature/FindersKeepers'', also largely sticks to this genre, until the very end, where it is revealed that Brady Hartfield (the villain from the first book) has gained telekinetic abilities after awakening from his coma. This sets up the third book, ''Literature/EndOfWatch'', in which Brady is once again the villain and fully uses his new psychic powers. And finally, the fourth installment, ''Literature/TheOutsider2018'', completely ditches the human villains and gives the series its first EldritchAbomination.**
''Literature/TheStand'' does this. The first third is a straight-forward Apocalypse-by-disease, then it becomes a supernatural thriller.
* ''Literature/{{Misery}}'': In-universe example. Paul Sheldon writes a series of cheesy romance novels featuring a Victorian bimbo named Misery Chastain. He despises the character for being a CanonSue and only continues writing her because it's his flagship series and the money it makes goes into the kids' college fund, so he has her killed off via DeathByChildbirth. When his greatest fan (who is also AxCrazy) finds out, she demands he write a new book bringing her BackFromTheDead that directly follows from the last one (he at first tries a straight {{Retcon}} but she dismisses it as cheating). He eventually comes up with the idea that Misery fell into a coma due to a bee-sting and was BuriedAlive, in effect turning the story into a Gothic PsychologicalHorror which reveals dark secrets in Misery's family line and the town. Paul eventually comes to the conclusion that this is the best book he has ever written.