A Japanese {{Manga}} spanning from 1996 to 1998, Oldboy is perhaps better known for the loosely-adapted [[Film/{{Oldboy 2003}} film version of the same name]].

Kidnapped without provocation, a man [[NoNameGiven identifying as Yamashita]] is kept in a tiny cell, with only a TV, bed and bathroom. Left with nothing to do but exercise and pass time, he spends ten years alone, only to find himself dressed, drugged and dumped in a public park without reason. Given plenty of money and a phone by his captors, Yamashita meets a young girl named Eri, finds his old friend Tsukamoto and even gets a job, but finds himself driven to track down those who imprisoned him.

Later developed into a highly successful Korean movie (by [[Creator/ParkChanWook Park Chan-wook]]) in 2003, the series was translated in 2005 following the film's international success.

This page desperately ''SugarWiki/{{needs more love}}.''

'''Please note that, like its film counterpart, this manga involves several major twists and reveals''' '''''so watch for spoilers.'''''
%%Since the real names of the protagonist and antagonist are used as a reveal, please refer to them as Yamashita and Alias Dojima outside of spoiler text.
!!This manga series contains examples of:

* AbsurdlyHighStakesGame: Alias Dojima and Yamashita gamble if the latter can figure out ''why'' he was imprisoned, with the stakes of [[spoiler:the loser dying (or, if Yamashita loses and runs, everyone he cares about dies).]]
* CrazyPrepared: Alias Dojima, who somehow has bugs planted in the right place beforehand on several occasions.
* CreepyChild: [[spoiler:Kakinuma. Even Yukio (read: '''his teacher''') harbored a dislike for him simply because he was so creepy.]]
* DisproportionateRetribution: [[spoiler: Kakinuma's quest for revenge is all a result of Goto ''pitying him when they were children.'']]
* DoesntLikeGuns: Yamashita, who willingly throws away a gun at one point to prevent RecklessGunUsage.
* DontYouDarePityMe: [[spoiler:The reason for Kakinuma imprisoning Goto is because he was the only person to ever pity him when they were children.]]
* DrivenToSuicide: [[spoiler:Kakinuma, who loses his gamble and decides to keep to his end of the bargain.]]
* GratuitousEnglish: Tsukamoto's bar is called "Moon Dog".
* TheJailer
* LeParkour: In one of the books, Yamashita loses one of Alias Dojima's thugs by running into a high building and ''jumping roof to roof.''
* NoNameGiven: The protagonist and antagonist, who go by the names Yamashita/Mister and "Alias Dojima" until their real names are revealed ([[spoiler:Shinichi Goto]] and [[spoiler:Takaaki Kakinuma]] respectively).
** Alias Dojima's spy never gets a real or fake name.
* PermaStubble: Yamashita [[spoiler:though he appears clean-shaven in the epilogue.]]
* PragmaticAdaptation: The premise remains the same between the manga and movie, but beyond that they differ completely. Even the [[TheStoic calm]] Yamashita from the manga is changed to the [[HairTriggerTemper almost psychopathic]] Oh Dae-su in the movie. Also, [[spoiler: no one except Kakinuma dies in the manga; in the film, there is literally a mountain of corpses left by Oh Dae-su]].
* LeftHanging: [[spoiler:Despite Eri having a second level of post-hypnotic suggestion that may still dictate her actions, the group never find out what it is due to Kyoko disappearing.]]
* RageBreakingPoint: [[spoiler:Both Goto and Yamashita invoke this, when pushed too hard and beaten respectively.]]
* SexySecretary: Kyoko Kataoka, Alias Dojima's assistant. [[spoiler:Her sexiness is even used to distract and control Tsukamoto when they start visiting Moon Dog.]]
* SmugSnake: Alias Dojima, who is constantly calm (even when [[spoiler: Goto snaps and starts punching him in the face]], he remains somewhat indifferent).
* TokenRomance: Yamashita and Eri. [[spoiler:It turns out it's a result of hypnosis.]] They get somewhat over it.
* TookALevelInBadass: Yamashita, who spent most of his ten-year imprisonment doing push-ups, sit-ups and shadow boxing. He even manages to beat up a group of thugs easily when he's released.
* VillainousBreakdown: [[spoiler:Kakinuma when Goto figures out why he imprisoned him.]]
* WhatNowEnding: [[spoiler:The epilogue of the series ends with Kakinuma dead, and Goto with Eri. However, Goto has a nightmare about Eri's second layer of hypnosis causing her to kill herself, prompting Goto to conclude that Kakinuma's game has yet to finish.]]
* WoundedGazelleGambit: Yamashita, wanting more money after being released, acts drunk to attract muggers [[TookALevelInBadass so he can mug them.]]