[[quoteright:200:http://static.tvtropes.org/pmwiki/pub/images/w2r157_twenty_thousand_leagues_under_the_sea_2985.jpg]]

''Twenty Thousand Leagues Under the Sea'' is an 1869 adventure novel by Creator/JulesVerne. It scores a solid 5 on MohsScaleOfScienceFictionHardness and has a strong focus on technology, existentialism, and marine biology.

During a visit to America, Professor Aronnax, a famous French marine biologist, is invited to join a [[YanksWithTanks US Navy]] expedition in the hunt for a mysterious sea monster (believed to be a giant narwhal) that has attacked and damaged two ships. Once they find the narwhal, it attacks, causing Aronnax, his trusty manservant [[TheStoic Conseil]] and Ned Land, the ship's [[CanadaEh Canadian]] harpoonist, to fall overboard (well, Conseil ''jumped'', to rescue the Professor). They clamber onto the only dry spot in the sea, namely the narwhal's back, expecting to drown as soon as it dives. Then a hatch opens...

The mysterious narwhal is in fact not a whale, but a high-tech electric submarine, owned and designed by the mysterious and eccentric [[NoNameGiven Captain Nemo]]. While refusing to put our heroes ashore, he lets them live, and takes them on a fantastic journey under the seas of the world, showing them the many wonders of the world beneath the waves. Aronnax finds himself torn between his passionate interest in marine biology and his desire for freedom - should he try to escape with his comrades or stay and find out ''why'' Nemo sails around the world, sinking British and American ships?

The novel has a sequel, ''TheMysteriousIsland'', which tells Nemo's BackStory.

Fun fact that people sometimes forget: the title refers to the distance the ''Nautilus'' travels horizontally over the course of the book, not the depth it dives to. 20,000 leagues vertically would be impossible, being 80,000 kilometers[[note]]Verne used the metric league, which is 4 km[[/note]], or twice the circumference of the Earth. The [[BlindIdiotTranslation translation is partly to blame]]; a closer translation would be ''Twenty Thousand Leagues Under the ''''Seas',''''' which is sometimes used in more modern translations. A ''SaturdayNightLive'' sketch with guest host Kelsey Grammar as Nemo [[LampshadeHanging lampshaded]] this misconception.

The book is now out of copyright and can be obtained from Project Gutenberg [[http://www.gutenberg.org/ebooks/2488 here]]. This translation, done by Verne scholar Frederick Paul Walter, is a modern, highly accurate translation of the book, free of the errors that many other editions of the book have. Alternatively, check out the most common edition [[http://www.gutenberg.org/ebooks/164 here]]. This translation, done by the Reverend Lewis Page Mercier, is widely considered to be the worst translation of the book; it is riddled with errors and censorship, as well as incorrect numbers (for example, the density of steel is given as .7 to .8 times that of water, while Verne really wrote 7.8 times that of water, which is the correct value). Sadly, it is also the most common translation - check your bookshelves for this version!

This also allowed life-long fan and mini-submarines builder Pat Regan to publish a sequel (mostly inspired by Disney's movie), titled [[http://tvtropes.org/pmwiki/pmwiki.php/Literature/Vulcanium ''Vulcanium'']]

The best-known adaptation of the novel is [[Film/TwentyThousandLeaguesUnderTheSea the 1954 live-action Disney film]].
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!!The novel ''Twenty Thousand Leagues Under the Sea'' shows examples of the following tropes:

* AbnormalAmmo: The Nautilus crew's armament of choice is an air-rifle that fires a glass bullet containing a small capacitor. When the glass shatters, the capacitor unleashes its charge, instantly killing the target.
* AboveGoodAndEvil: What Captain Nemo claims to be.[[spoiler: He really isn't]]. See {{Ubermensch}} below.
* AbsentMindedProfessor: Aronnax has this a few times. One chapter has him declare a book he's been engrossed in for several hours as utterly brilliant, which Conseil is bemused by. When Aronnax asks what's so funny, Conseil tells him to check the spine to see who wrote it... turns out, it was Aronnax himself, and he'd completely forgotten about it.
* AnAesop:
** TechnologyIsEvil because HumansAreBastards: JustThinkOfThePotential to do good a CoolBoat like the Nautilus! But before that, It will be used for SubmarinePirates as a WeaponOfMassDestruction.
** A WeaponOfMassDestruction is an ArtifactOfDoom. NoManShouldHaveThisPower and if he does, he becomes an {{Ubermensch}}.
** No matter what a wholesome NiceGuy you genuinely are, if you become an {{Ubermensch}} because you have a WeaponOfMassDestruction, for a time you will be TheAntiNihilist, but slowly but surely you will become a NietzscheWannabe.
* AffablyEvil: Deconstructed by Captain Nemo, who is a genuinely noble NiceGuy who has access to technology enjoyed by none else. How can a truly good man cross the MoralEventHorizon? [[VillainousBreakdown Because he is slowly but surely losing his sanity through the novel, and in the end he becomes a]] DeathSeeker.
* AllLovingHero: [[TheProfessor Professor Aronnax]] is a humble WideEyedIdealist scientist that already had won the UndyingLoyalty of Counseil before he comes to the Nautilus, he also makes [[IdiotHero Ned Land]] do a MoreExpendableThanYou sacrifice when they are in the Pole, and he is ultimately the reason why Captain Nemo gets his VillainousBreakdown when Aronnax discovers the Nautilus is a WeaponOfMassDestruction.
* AlmostOutOfOxygen: When the Nautilus is trapped under the Antarctic ice. Verne, however, did his research. Oxygen is not a problem, due to the Nautilus having plenty of electricity and water around, but without caustic potash to bind the carbon dioxide the heroes are screwed anyway.
* AntiVillain: Nemo. His hatred of the British is perfectly understandable, given his BackStory. However, [[MoralEventHorizon attacking civilians]] for happening to be on a ship flying the wrong colours...
** And the fact that he is holding everyone captive at that. He's pretty much a crystal clear WellIntentionedExtremist.
* ArtifactOfDoom: The Nautilus is this for Captain Nemo: by using it as a WeaponOfMassDestruction, Nemo discovers that WithGreatPowerComesGreatInsanity
* {{Atlantis}}: Captain Nemo shows Professor Aronnax the ruins of Atlantis.
* AtlantisIsBoring: There is a discussion over whether this trope applies or not to this novel.
* AwesomeButImpractical: Discussed. When Nemo is telling Aronnax about his vast riches, extracting gold from seawater is mentioned, but it would cost so much as to turn little, if any, profit.
* BadAss: Pretty much everyone, considering the fact that they beat off a 50-foot ''giant squid'' armed only with axes and harpoons.
** Make that a ''dozen'' giant squid. Never mind that squid of any size are completely helpless out of water, of course...
* BattleButler: Conseil.
* BeardOfEvil: Nemo is depicted with a beard in the [[Film/TwentyThousandLeaguesUnderTheSea 1954 Disney film version]] (probably the most well-known adaptation) and pretty much every adaptation afterwards.
** He had a beard before that as well, in the 1916 black and white silent adaptation (which merged it with the sequel, TheMysteriousIsland into one story, as if the events all took place simultaneously, though the sequel was supposed to be many years later), Nemo has a beard, as well as wearing {{Blackface}}.
** The beard already appeared in the original illustrations of the book, since the artist used Colonel Charas as a model - fitting as Charas' life was somewhat similar to Nemo's, and he may also have been Verne's inspiration for the character.
* BeautyEqualsGoodness: Lampshaded when WideEyedIdealist Aronnax uses [[ScienceMarchesOn physiognomy to justify]] that a stocky character is a fool and the good–looking man is someone good, but rethinks this theory when the good–looking man (Captain Nemo) left him starving with their companions in a cell.
--> ''A disciple of such character–judging anatomists as [[ScienceMarchesOn Gratiolet or Engel could have read this man's features like an open book]]. Without hesitation, I identified his dominant qualities—self–confidence, since his head reared like a nobleman's above the arc formed by the lines of his shoulders, and his black eyes gazed with icy assurance; calmness, since his skin, pale rather than ruddy, indicated tranquility of blood; energy, shown by the swiftly knitting muscles of his brow; and finally courage, since his deep breathing denoted tremendous reserves of vitality.''
--> ''I might add that this was a man of great pride, that his calm, firm gaze seemed to reflect thinking on an elevated plane, and that the harmony of his facial expressions and bodily movements resulted in an overall effect of unquestionable candor—according to the findings of physiognomists, those analysts of facial character.''
--> ''[[IsThatWhatTheyreCallingItNow I felt "involuntarily reassured" in his presence]], and this boded well for our interview.''
* BerserkButton: Ned Land discovers that he must never surrender to TheEmpire while Nemo is TheCaptain at the Nautilus.
* BigEater: Ned Land, whose only interest in an any wildlife species seems to run entirely in a culinary direction.
* TheButcher: Ned Land accuses Nemo of this when Nemo [[KickTheDog Kicks The Cachalots]] in a massacre. (See TheHunter).
* BrokenPedestal: After spending the novel swimming in StockholmSyndrome for Captain Nemo, Aronnax sees him crossing the MoralEventHorizon in a terrible KickTheDog moment. And yet...
-->''I returned to the saloon, fearing and yet hoping to see Captain Nemo, wishing and yet not wishing to see him. What could I have said to him? Could I hide the involuntary horror with which he inspired me? No. It was better that I should not meet him face to face; better to forget him. And yet—''
* CanadaEh: Okay Jules, we get it! Ned Land is from Canada! You don't have to keep telling us twice per page!
** Inverted in that he's loud, arrogant, and rather meatheaded (and whistles "''Yankee Doodle''").
* TheCaptain: Deconstructed with Nemo, he is so charismatic a captain and so loved by his crew that nobody notices his VillainousBreakdown.
* CharacterFilibuster: Arronax tends to go off on long digressions about various species of marine life he's observed, interrupting the adventure story of which he's one of the main characters.
* ClosedCircle: Even when the Nautilus travels around the whole world, [[TheProfessor Professor Aronnax]],[[BattleButler Conseil]] and [[IdiotHero Ned Land]] [[EnclosedSpace are confined to the submarine]]. They only talk with Captain Nemo (all the other crew talk a secret language).
* CompletelyUnnecessaryTranslator: A variation occurs when [[TheProfessor Professor Aronnax]], [[BattleButler Conseil]] and [[IdiotHero Ned Land]] failing to understand the language used by their captors, try to talk to them in their respective native languages (French, German (Conseil is Dutch, but presumably uses German because Dutch is a very rare language outside of The Netherlands) and English, respectively). When their captors didn’t react, Aronnax atttempted to speak Latin without success. In a second interview, the man that later presented himself as Captain Nemo told them:
-->''...After some moments of silence, which not one of us dreamed of breaking, "Gentlemen," said he, in a calm and penetrating voice, "I speak French, English, German, and Latin equally well. I could, therefore, have answered you at our first interview, but I wished to know you first, then to reflect…”''
* ConLang: Subverted because even when the Nautilus crew uses a language that [[TheProfessor Professor Aronnax]] cannot recognize, Verne didn’t bother himself making any words of it except ''"Nautron respoc lorni virch."'' that Aronnax thinks must mean: ''"There's nothing in sight."''. Aronnax describes the language like this:
-->'' "… a language I didn't recognize. It was a sonorous, harmonious, flexible dialect whose vowels seemed to undergo a highly varied accentuation".''
** Given that the Nautilus crew is a NGOSuperpower, it makes sense this language is a ConLang '''Completely Original''', designed to substitute all the other “continental” languages that were original to each of the crew countries that the crew has abandoned. Aronnax observes that just moments before his death, one of the crew forgets to use that ConLang and ask for help in French. A hungry Ned Land also theorizes:
--> ''"Don't you see, these people have a language all to themselves, a [[ConLang language they've invented just to cause despair in decent people who ask for a little dinner!]] Why, in every country on earth, when you open your mouth, snap your jaws, smack your lips and teeth, isn't that the world's most understandable message? From Quebec to the Tuamotu Islands, from Paris to the Antipodes, doesn't it mean: I'm hungry, give me a bite to eat!"''
* ConspiracyTheorist: PlayedForLaughs with Ned Land: As a professional fisher, he doesn’t believe in Sea monsters (giant narwhales or octopus), but he believes that his captors [[ImAHumanitarian could be cannibals]], that the language spoken in the Nautilus is a [[AncientConspiracy conspiracy to let him die of hunger]] (see ConLang) and in ArtificialHuman:
--> "Haven't seen or heard a thing!" the Canadian replied. "I haven't even spotted the crew of this boat. By any chance, could they be electric too?"
--> "Electric?"
--> "Oh ye gods, I'm half tempted to believe it!"
* CoolShip: The Nautilus, which has a greater range than any existing non-nuclear submarine.
* DangerouslyGenreSavvy: A subtle example: Captain Nemo knows the PowerTrio will attempt a GreatEscape because he desn't want to impose ThePromise on them to keep the Nautilus safe. So he only allows the PowerTrio to explore islands without any connection to civilization, and navigates on the surfaces of the seas that are either not frequented by ships or are actually affected by a natural event that could cause the death of the escapees (like a submarine eruption or the Maelstrom).
* DeathSeeker: As Nemo's mental health deteriorates through the course of the story, he becomes more reckless.
* DeliberateValuesDissonance: InUniverse: [[GreatWhiteHunter Ned Land]] asks Captain Nemo’s permission to hunt some whales. Nemo denies it and he accuses Ned of being an EgomaniacHunter. [[HypocriticalHumor Next they see some cachalots and Nemo]] [[KickTheDog destroys them using the Nautilus’ spur]]. When Ned accuses Nemo as being TheButcher, Nemo answers that [[WellIntentionedExtremist the cachalots were mischievous creatures]] and [[IDidWhatIHadToDo the Nautilus is his weapon]]. Verne shows us that no matter how much mistaken is the philosophy of GreatWhiteHunter, they will never do the damage that the Ubersmench can do using science.
* DisproportionateRetribution: Conseil and Arronax geek out over a seashell that twists left-handedly instead of to the right. When a lucky shot from one of the attacking natives shatters it, Conseil promptly picks up a gun and shoots the man.
* DysfunctionJunction: There are only four principal characters in the novel due to the ClosedCircle: [[BattleButler Conseil]] has so much UndyingLoyalty that he considers himself an extension of his employer. [[TheProfessor Professor Aronnax]] practically swims in StockholmSyndrome, Captain Nemo has a slow VillainousBreakdown caused by him, a good man, crossing once and again the MoralEventHorizon. [[OnlySaneMan Ned Land]] slowly [[GoMadFromTheIsolation Goes Mad From The Isolation]].
* DumbassHasAPoint: In all of the book, [[IdiotHero Ned Land]] opines Captain Nemo is a despot and the PowerTrio must attempt the GreatEscape as soon as possible. [[TheProfessor Professor Aronnax]] and [[BattleButler Conseil]] are impressed with Nemo and their incredible voyage, and it's not until they see Nemo crossing the MoralEventHorizon before they realize Ned was the OnlySaneMan.
* EgomaniacHunter: Captain Nemo accuses Ned Land of being one when Ned ask him permission to hunt whales only because ''he wants to''.
--> "And to what purpose?" replied Captain Nemo; "only to destroy! We have nothing to do with the whale-oil on board."
--> "But, sir," continued the Canadian, "in the Red Sea you allowed us to follow the dugong."
--> "Then it was to procure fresh meat for my crew. [[ARealManIsAKiller Here it would be killing for killing's sake. I know that is a privilege reserved for man, but I do not approve of such murderous pastime]]. In destroying the southern whale (like the Greenland whale, an inoffensive creature), your traders do a culpable action, Master Land. They have already depopulated the whole of Baffin's Bay, and are annihilating a class of useful animals. Leave the unfortunate cetacea alone. They have plenty of natural enemies—cachalots, swordfish, and sawfish—without you troubling them."
* {{Egopolis}}: Captain Nemo displays a variant when he claims ''an entire continent'' for himself, acting like a sovereign (but see ExactlyWhatItSaysOnTheTin below):
--> ...Well now! In 1868, on this 21st day of March, I myself, Captain Nemo, have reached the South Pole at 90°, and I hereby claim this entire part of the globe, equal to one–sixth of the known continents."
--> "In the name of which sovereign, Captain?"
--> ''"In my own name, sir!"''
--> So saying, Captain Nemo unfurled a black flag bearing a gold "N" on its quartered bunting. Then, turning toward the orb of day, whose last rays were licking at the sea's horizon:
--> "Farewell, O sun!" he called. "Disappear, O radiant orb! Retire beneath this open sea, and let six months of night spread their shadows over ''my new domains!"''
* EnclosedSpace: Subverted because Nemo let the PowerTrio explore land where an escape would be more dangerous than Nemo's [[SubStory hospitality in the Nautilus]].
* EvenEvilHasLovedOnes: Aronnax at one point finds Nemo privately weeping in front of a portrait of (what is implied to be) his dead wife and children.
* ExactlyWhatItSaysOnTheTin: While the earlier English translations tend to mess up many of Verne's measurements, the original French version is an account of a journey of 20,000 ''lieues'', which is translated into English as "leagues". As is common with many early measurements, the exact definition of a "lieue" or "league" varies, but there is internal evidence in the story that Verne was using a metric ''lieue'' of 4 kilometres. (On multiple instances he gives distances in both lieues and nautical miles, which correspond exactly, if a "lieue" is 4km.)
** Nemo reclaims the South Pole in his name. That means that ''[[BilingualBonus no one]]'' owns the South Pole.
* ExecutiveMeddling: Verne originally wrote Nemo as a Polish nobleman, who lost his family to the Russians. Verne's publisher was wary of portraying the Russians (France's ally at the time) in a negative light, and didn't want to lose sales in Russia, so he persuaded Verne to make Nemo's nationality a mystery [[note]]at least until the sequel novel, ''TheMysteriousIsland'', where Nemo is revealed to have been an Indian prince who lost his family to the British[[/note]]. Also an example about TropesAreNotBad: Revealing Nemo's BackStory left him only a menace against a single nation, but leaving Nemo's nationality anonymous not only defines him (Nemo means Nobody) but also makes the reader realize that any nation, even the reader's nation, [[ObligatoryWarCrimeScene could have committed the alleged crimes against Nemo and his family]]. Even more, [[AnyoneCanDie it implies that no ship of any nationality was safe for navigation]].
* {{Expy}}: Captain [[MeaningfulName Nemo]] is an expy for [[Literature/TheOdyssey Odysseus]]: A great sailor, TheCaptain of a ship who commanded a RedShirt crew, that claimed he was “No One”, who fought against beings he cannot defeat (Nemo against TheEmpire, Odysseus against JerkassGods) motivated by YouCantGoHomeAgain.
* {{Fiction 500}}: Captain Nemo brags to [[TheProfessor Professor Aronnax]] that he is so rich, he could pay France's entire national debt. Later Aronnax discovers this is the truth in Vigo Bay: [[CoolShip The superior tech of the Nautilus]] lets Nemo reclaim all the treasures lost to man in shipwrecks, before any other treasure hunter.
* TheFinalFrontier: Subverted: In this book it is not space, but the unknown sea, the only place on earth where man could be free (and it remains the same more than one hundred years later) as Nemo says:
-->''"...The sea is a vast pool of nature. Our globe began with the sea, so to speak, and who can say we won't end with it! Here lies supreme tranquility. The sea doesn't belong to tyrants. On its surface they can still exercise their iniquitous claims, battle each other, devour each other, haul every earthly horror. But thirty feet below sea level, their dominion ceases, their influence fades, their power vanishes! Ah, sir, live! Live in the heart of the seas! Here alone lies independence! Here I recognize no superiors! Here I'm free!"''
* ForeignQueasine: Subverted: The food served ship-side is fish and seafood only, and the heroes are somewhat reluctant to try lightly grilled sea-cucumbers and dolphin-liver ragout. However, Nemo's chef is apparently something of a genius and can crank out very tasty meals of whatever he is given to work with.
** Ned Land, however, [[RealMenEatMeat still prefers red meat]], [[ManlyMenCanHunt and goes hunting on land at every opportunity]].
* {{Foreshadowing}}:
** The first time he sees Captain Nemo, Aronnax instinctively trusts him because BeautyEqualsGoodness, but later [[BrokenPedestal reevaluates his beliefs when it that same man is going to leave them starving in a cell]]. Cue the finale of the novel…
** Looking at the marvels of the South Pole, Ned Land says that TheseAreThingsManWasNotMeantToKnow… in just the next chapter, the Nautilus is AlmostOutOfOxygen.
** [[GreatWhiteHunter Ned Land]] is ashamed when [[{{Ubermensch}} Captain Nemo]] [[KickTheDog Kicks The Cachalots]] in a terrible massacre. At the end of the novel, Nemo will KickTheDog again…
* ForScience: While Captain Nemo's motivation is For {{Revenge}}, [[TheProfessor Professor Aronnax]] is willing to sacrificing [[ProfessorGuineaPig his freedom for the rest of his life]] ForScience. Thankfully, he is not [[GuineaPigFamily willing to sacrifice his friends’ freedom]].
* FreudianExcuse: Nemo. [[spoiler: His wife and children were executed by the British because he fought on the losing side during the [[http://en.wikipedia.org/wiki/Indian_Rebellion_of_1857 Sepoy Uprising]].]]
* FreudianSlip: Aronnax, whilst having a discussion about oysters and pearls shortly after being informed that they were going shark hunting, says that some larger oysters have been claimed to contain up to 150 ''sharks''.
* FromMyOwnPersonalGarden: Captain Nemo informs his prisoners that everything they are eating was taken from the ocean. Exaggerated because everything there is in the Nautilus is from the Ocean: the energy, the clothes, the cigars...
* GiantSquid: The crew of Nautilus (and Ned Land) fight a giant squid that has wrapped itself around the submarine. It is the most recognisable point after Nemo and the Nautilus themselves and is a standard fixture in any adaptation.
* GildedCage: Captain Nemo explains to Aronnax:
-->''"You said that we should be free on board."''
-->''"Entirely."''
-->''"I ask you, then, what you mean by this liberty?"''
-->''"Just the liberty to go, to come, to see, to observe even all that passes here save under rare circumstances—the liberty, in short, which we enjoy ourselves, my companions and I."''
-->''It was evident that we did not understand one another.''
-->''"Pardon me, sir," I resumed, "but this liberty is only what every prisoner has of pacing his prison. It cannot suffice us."''
-->''"It must suffice you, however."''
* GoMadFromTheIsolation: After seven months of not talking [[ClosedCircle with any other human being]] except Captain Nemo, [[TheProfessor Professor Aronnax]] and BattleButler Conseil, the independent and BookDumb Ned Land, not interested in submarine investigation, is slowly going insane.
--> I'll also mention that the Canadian, at the end of his strength and patience, made no further appearances. Conseil couldn't coax a single word out of him and feared that, in a fit of delirium while under the sway of a ghastly homesickness, Ned would kill himself. So he kept a devoted watch on his friend every instant.
* GreatEscape: Aronnax, Counseil and Ned Land are [[EnclosedSpace prisoners in the Nautilus]]. To regain their freedom, they must attempt a succesful GreatEscape because there will not be a second chance.
* GreatWhiteHunter: Ned Land.
* HandshakeRefusal: [[TheProfessor Professor Aronnax]] gets this treatment with Captain Nemo. Nemo doesn't distrust [[WideEyedIdealist Aronnax]], its' just to show how far Nemo has been subject to MaddenIntoMisanthropy:
--> ''I thought the commander would offer me his hand, to seal our agreement. He did nothing of the sort. I regretted that.''
* HaveAGayOldTime: Goes along with the Stockholm Syndrome and the HoYay. For example;
--> ''This man was certainly the most admirable specimen I had ever met.''
* HeelRealization: After Captain Nemos KickTheDog moment, WideEyedIdealist Aronnax realizes the true price of his travels with Captain Nemo:
--> ''"He had made me, if not an accomplice, at least an eyewitness to his vengeance! Even this was intolerable."''
* HeWhoFightsMonsters: Captain Nemo MajoredInWesternHypocrisy and wants revenge against TheEmpire. He creates an NGOSuperpower with a OddlySmallOrganization with her own ConLang, [[EgoPolis he claims a continent in his name,]] creates the Nautilus to conquest TheFinalFrontier (the sea) and to use it as a WeaponOfMassDestruction, [[FromMyOwnPersonalGarden insists in only using sea related products]], and the prisoners he considers valuable are placed in a GildedCage but those who not are [[KickTheDog mercilessly destroyed]]. Trying to destroy TheEmpire, he ends [[StartMyOwn creating a society]] [[MilkmanConspiracy very much like it]].
* HeKnowsTooMuch: The reason Aronnax, Conseil and Ned Land will remain prisoners of the Nautilus and cannot come back to Civilization. Ever. (Captain Nemo lets them abandon the Nautilus and explore land, but it is always on uncivilized shores). Captain Nemo explains:
-->''"... You came to surprise a secret which no man in the world must penetrate—the secret of my whole existence. And you think that I am going to send you back to that world which must know me no more? Never! In retaining you, it is not you whom I guard—it is myself."''
* HiddenDepths: All of the main characters, from Ned Land (who is surprisingly knowledgeable about marine life despite his BookDumb personality) to Nemo (see WickedCultured) show this at times.
* HumansAreBastards & EverythingsEvenWorseWithSharks: Captain Nemo adheres to this belief:
--> "Your dead sleep quietly, at least, Captain, out of the reach of sharks."
--> "Yes, sir, of sharks and men," gravely replied the Captain.
* TheHunter: Ned Land accuses Nemo of being TheButcher after observing [[KickTheDog him massacring the cachalots]]. Captain Nemo claims to be hunting dangerous plagues.
-->''"Well, sir," replied the Canadian, whose enthusiasm had somewhat calmed; "it is a terrible spectacle, certainly. [[TheHunter But I am not a butcher. I am a hunter,]] [[TheButcher and I call this a butchery]]."''
-->''"[[TheHunter It is a massacre of mischievous creatures,"]] replied the Captain; "and the Nautilus is not a butcher's knife."''
* HypercompetentSidekick: Conseil, at least when it comes to cataloging wildlife.
* ImADoctorNotAPlaceholder: After Nemo [[KickTheDog Kicks The Cachalots]] and asks Ned Land his opinion, Ned claims to be a hunter and not a butcher.
* IAmTheNoun: Captain Nemo:
--> "I am the law, and I am the judge! I am the oppressed, and there is the oppressor!"
* IdiotHero: Verne's writing constantly informs us (and Conseil and Aronnax repeatedly lampshade) that Ned Land is a HotBlooded, GreatWhiteHunter, BigEater RealMenEatMeat BookDumb BadAss [[ArsonMurderAndJaywalking who is from ]] [[CanadaEh Canada]]. [[spoiler: Ned Land's personality also makes him the OnlySaneMan capable of resisting Captain Nemo's charisma]].
* ImAHumanitarian: Ned Land (jokingly) threatens to eat Conseil if he doesn't get something other than fish to eat soon.
* ImpaledWithExtremePrejudice: The Nautilus' primary weapon is a ramming spur. Nemo has no compunctions about using it against wildlife he doesn't like or against shipping that's flying the flags of nations he doesn't approve of.
* IsItSomethingYouEat: Stock line from Ned Land, whose only interest in wildlife is culinary.
* JustBetweenYouAndMe: Subverted because Nemo never shares the evil part of his EvilPlan with Aronnax, [[AntiVillain just because he is ashamed of it]]. However, Nemo is constantly sharing all the information about the Nautilus and his scientific investigations about the Sea with [[TheProfessor Professor Aronnax]], not because he will kill him, but because Nemo pretends that [[GildedCage Aronnax will never abandon the Nautilus]].
-->''Is it indiscreet to ask how you discovered this tunnel?"''
-->''"Sir," the captain answered me, "there can be no secrets between men who will never leave each other."''
-->''I ignored this innuendo and waited for Captain Nemo's explanation.''
* KickTheDog: Captain Nemo is implied to have destroyed ships with civilians and military crew, but the act of following up an attack with the Nautilus observing the horrible death of all the unnamed ship's crew ''on purpose, without losing any detail'', is when Nemo crosses the MoralEventHorizon.
** Captain Nemo [[KickTheDog Kicks The Cachalots]] in a terrible massacre:
-->''... The sea was covered with mutilated bodies. A formidable explosion could not have divided and torn this fleshy mass with more violence. We were floating amid gigantic bodies, bluish on the back and white underneath, covered with enormous protuberances. Some terrified cachalots were flying towards the horizon. The waves were dyed red for several miles, and the Nautilus floated in a sea of blood..''
* MaddenIntoMisanthropy: When Aronnax calls out Captain Nemo about the cruelty implied in never letting them go out of the Nautilus, Captain Nemo answers:
-->''"What! We must give up seeing our homeland, friends, and relatives ever again?"''
-->''"Yes, sir. But giving up that intolerable earthly yoke that some men call freedom is perhaps less painful than you think!"''
* MajoredInWesternHypocrisy:
--> "You're an engineer, then, Captain Nemo?"
--> "Yes, professor," he answered me. "I studied in London, Paris, and New York back in the days when I was a resident of the Earth's continents."
* MeaningfulName: "Nemo" is Latin for "no one".
** Also Greek for "I give what is due".
** Ned Land. He wishes more strongly than any of the other captives to return to ''terra firma''.
** ''Conseil'' is French for "counsel", meaning advice. Inverted because Conseil doesn't like to give advice. This is lampshaded by the Professor himself.
* MeaningfulRename: Captain Nemo gave himself this name after he left the land.
* MessageInABottle: Captain Nemo plans to use one to assure his research is not lost:
--> ''"Here, Professor Aronnax, is a manuscript written in several languages. It contains a summary of my research under the sea, and God willing, it won't perish with me. Signed with my name, complete with my life story, this manuscript will be enclosed in a small, unsinkable contrivance. The last surviving man on the Nautilus will throw this contrivance into the sea, and it will go wherever the waves carry it."''.
* MilkmanConspiracy: Deconstructed by the Nautilus crew, a [[StartMyOwn truly new society]] with NGOSuperpower status is composed of… [[OddlySmallOrganization less than sixty persons]]. Less than four years after its creation, their existence has been discovered by TheEmpire, [[TheWarOnTerror all the Western nations have organized against them and are chasing them implacably]], [[RealityEnsues their numbers dwindle because of this and because of normal accidents on the sea]], and their leader, [[TheCaptain charismatic Captain Nemo]], not only is bitterly conscious that their days are numbered (he plans to use a MessageInABottle so all his sea research could be found), [[WithGreatPowerComesGreatInsanity but is slowly breaking down due to using a]] WeaponOfMassDestruction to cross the MoralEventHorizon repeatedly.
* MistakenNationality: Subverted, The novel emphasizes the mystery of Captain [[MeaningfulName Nemo]] hiding his nationality. Even when his eyes are black and his skin is pale, Aronnax lampshades that he is not sure invoking InterchangeableAsianCultures
-->''”I admit that the nationality of the two strangers is hard to determine. Neither English, French, nor German, that is quite certain. However, I am inclined to think that the commander and his companion were born in low latitudes. There is southern blood in them. But I cannot decide by their appearance whether they are Spaniards, [[InterchangeableAsianCultures Turks, Arabians, or Indians]]"''
* MobileMenace: The power of the Nautilus: In 1869, a submarine can arrive to any part of the seas and destroy any ship:
--> ''Moving within the moving element! It was a highly appropriate motto for this underwater machine, so long as the preposition in is translated as within and not upon.''
* MoreExpendableThanYou: Played straight by Conseil and Ned Land when they give Aronnax some precious oxygen in the AlmostOutOfOxygen situation, then conversed:
--> ''"Good lord, Professor," Ned Land answered me, "don't mention it! What did we do that's so praiseworthy? Not a thing. It was a question of simple arithmetic. Your life is worth more than ours. So we had to save it."''
* MotiveRant: Captain Nemo gives one to [[TheProfessor Professor Aronnax]] when he tries to convince him not to KickTheDog, and could be considered the beginning of Nemo's VillainousBreakdown:
--> "[[IAmTheNoun I am the law, and I am the judge! I am the oppressed, and there is the oppressor!]] Through him I have lost all that I loved, cherished, and venerated -- country, wife, children, father, and mother. I saw all perish! All that I hate is there! Say no more!"
* MrExposition: [[TheProfessor Professor Aronnax]] and Captain Nemo take turns at it.
* NeverFoundTheBody: Aronnax wonders if [[spoiler:Nemo and his ship survived the maelstrom and still pursues his submarine vengence, or whether he and his crew did indeed perish.]]
* NGOSuperpower: Captain Nemo's organization, the crew of the Nautilus: [[CoolShip The Nautilus]] lets him loot enough submarine treasures to put him in {{Fiction 500}}, [[YourTerroristsAreOurFreedomFighters he can finance political insurrections like the Cretan rebellion]], [[{{Egopolis}} he claims the South Pole in his name]], he destroys the ships of an unnamed [[TheEmpire Imperialistic Nation]] with total impunity. His crew is composed of men who have no place in earth and [[ConLang they have invented their own language]].
* NoNameGiven: Nemo's real name is not revealed.
** ...until the sequel, that is: his name is [[spoiler: Prince Dakkar.]]
* NotThatKindOfDoctor: Arronax is asked to treat a crewman with a massive head wound, but all he can do is confirm that he'll be dead in the hour.
* OddlySmallOrganization: For an NGOSuperpower capable of helping the Cretan Insurrection, destroying [[TheEmpire The Empire's]] ships and with its own [[ConLang language]], the Nautilus crew is small: We only see Captain Nemo, his NumberTwo, and two unfortunate crewmen that die in the novel. And because they have severed all contact with inhabited continents, there will be no more crewmen. Aronnax made a calculation about less than sixty people:
--> ''"... Which is tantamount to saying that the air contained in the Nautilus would be exactly enough for 625 men over twenty–four hours."''
--> ''"625!" Ned repeated.''
--> ''"But rest assured," I added, "that between passengers, seamen, or officers, we don't total one–tenth of that figure."''
* OldRetainer: Conseil may only be 30, but his devotion to "[[GratuitousFrench monsieur le professeur]]" is mildly disturbing.
* {{Omniglot}}: Nemo is fluent in French, English, German, and Latin, and probably far more languages.
* PetTheDog: Nemo has several such moments, including sending assistance to Cretan rebels, saving the life and giving some pearls to a poor fisherman and [[spoiler:weeping over the memory of his dead wife.]] See AntiVillain.
* PoliteVillainsRudeHeroes: This is the dynamic between [[WickedCultured Captain Nemo]] and [[IdiotHero Ned Land]]. Nemo is AffablyEvil, and Ned Land doesn’t pass any chance to insult Nemo, no matter how petty.
* {{Polyglot}}: Nemo is fluent in French, English, German, and Latin, and claims to speak many other languages. He also has a strange language of his own that he and his crew use.
* PowerTrio: Conseil (superego), Professor Aronnax (ego), Ned Land (id).
* ProfessorGuineaPig: In a variation, [[TheProfessor Professor Aronnax]] is willing to sacrifice his own freedom for the rest of his life [[ForScience for the rare chance to discover all the sea’s secret in the Nautilus]].
* RaceLift: As explained in MysteriousIsland, Nemo is [[spoiler:an Indian prince]], but was originally envisioned as being from Poland (which the original illustrations portray him as).
* RageAgainstTheHeavens: Captain Nemo at times. See FreudianExcuse.
* RammingAlwaysWorks: Why the Nautilus needs a custom-built prow.
* RealMenEatMeat: A problem for Ned Land, who is a most manly man, and the Nautilus rarely goes even remotely close to shore.
** He does eventually get some pork... and promptly stops wailing about not having meat when they almost are murdered by natives.
* TheRemnant: Nemo and the Sepoy Uprising.
* TheReveal:
** There is no sea monster, it was a submarine.
** The last part of the book shows us exactly what Captain Nemo [[KickTheDog was using the Nautilus for when he asked his passengers to be in their cells]].
* RightBehindMe: In one scene, Aronnax is talking about a giant squid that had been sighted a few years earlier when Conseil, looking out the window, starts asking questions like, "Weren't its eyes prominently placed and considerably enlarged?"
* {{Satire}}: Very Juvenalian, the novel satirizes [[TheEmpire Imperialism]]: The Nautilus itself is a parody of TheEmpire - an OddlySmallOrganization that manages to be an NGOSuperpower, their members [[FromMyOwnPersonalGarden only consume sea products]] and [[ConLang speak only their own language]], but we never know any of them; they are nothing more than nameless masses. The only one who matters is Captain Nemo (the Emperor), who [[{{Egopolis}} claims an entire continent in his name]] and constantly crosses the MoralEventHorizon [[AboveGoodAndEvil for no other reason than because he can.]] The three prisoners personify a conquered nation's attitudes about TheEmpire: [[StockholmSyndrome Aronnax is the high class, who tries to get all the knowledge he can from the Empire]], [[TrueNeutral Conseil is the middle class, who passively accepts his loss of freedom as something inevitable and doesn’t want to make a decision without the approval of the high class,]] and [[ChronicBackStabbingDisorder Ned Land is the lower class who rebels constantly and uselessly]]. However, after seeing Nemo’s KickTheDog moment with his WeaponOfMassDestruction, the three classes agree that [[StartMyOwn Nemo’s empire]] [[HeWhoFightsMonsters is as bad as any other]].
* ScienceIsBad: Subverted because the book shows us all the good things the Nautilus can accomplish. Only after TheReveal, Aronnax’s HeelRealization lets him know that those good things can’t justify the terrible violence.
* ScienceMarchesOn:
** The chapter ''"Sperm Whales and Baleen Whales"'' has Nemo use the ''Nautilus'' to rescue some Baleen Whales by slaughtering a pod of Sperm Whales, that Nemo calls: "cruel, destructive beasts, and they deserve to be exterminated." A couple of chapters later the ''Nautilus'' has its infamous encounter with giant squid: [[{{Irony}} animals that we now know are favourites in the Sperm Whale's diet. They do not eat other species of whale.]]
** The North Pole is placed in the Arctic Ocean. The South Pole is placed in Antartica, a sheet of ice thousands of feet thick, and most of it on a solid continent. The Nautilus could have reached the North Pole[[note]]and indeed, the USS Nautilus (America's first nuclear sub and namesake of the vessel in this book) did reach the Pole by travelling under the Arctic Ocean[[/note]], but not the South Pole.
** The other Wiki notices that [[http://en.wikipedia.org/wiki/Physiognomy#Modern_physiognomy Physiognomy]] (see BeautyEqualsGoodness) fell from favor in the 20th century, but is now being revived once more.
** Electricity being presented as an amazing source of energy, these days it's commonplace.
* SeriesContinuityError: Much of the information presented about Captain Nemo and his career in ''TheMysteriousIsland'' (at least the dates) doesn't make ''any sense at all'' when compared to the text of ''Twenty Thousand Leagues''.
* ShoutOut: At an early point in the book, the narration mentions a white whale named "MobyDick".
** There's also a reference to Creator/EdgarAllanPoe's ''Literature/TheNarrativeOfArthurGordonPymOfNantucket''.
** The entire ending is likely to be a ShoutOut to another Creator/EdgarAllanPoe short story, 'A Descent into the Maelstrom', considering how much of an influence Poe was on Verne's writing.
* ShownTheirWork: Holy crap, does Verne ever do this. The narrative reaches ''MobyDick'' levels of textbook-ness at times.
** Leading to a lot of ScienceMarchesOn. A ''lot'' of the work, while reasonable from a nineteenth century perspective, is downright wrong.
* SpoilerTitle: Aronnax wonders constantly when they might be able to escape, before mentioning how far they've traveled. Clearly they can't until they've gone 20,000 leagues.
* StartMyOwn: A lesser man would just [[MaddenIntoMisanthropy become jaded]] and cut all ties with society, but Captain Nemo [[StartMyOwn starts his own society]] recruiting [[MaddenIntoMisanthropy other jaded men]] who hate TheEmpire, training them to build and operate [[CoolShip the Nautilus]], [[ConLang speak their own language]], [[FromMyOwnPersonalGarden obtain all their resources from the sea]], [[EgoPolis claim the South Pole]], [[YourTerroristsAreOurFreedomFighters finance the Cretan Rebellion and converting themselves]] into an NGOSuperpower.
-->''"if I can trust my hunches, if I truly understand the captain's way of life, his Nautilus isn't simply a ship. It's meant to be a refuge for people like its commander, people who have severed all ties with the shore."''
* StockholmSyndrome: One of the rare non-romantic examples, outside of HoYay. (In fact, there are practically no women in the book at all.)
* SubStory: The TropeMaker.
* SubmarinePirates: The TropeMaker.
* SuspiciouslySpecificDenial: When Captain Nemo asks the PowerTrio [[ThePromise to promise]] not trying to see… ''“something they must not see”'', he could not phrase it without sounding sinister and exciting Aronnax' suspicions:
-->'' It's possible that certain unforeseen events may force me to confine you to your cabins for some hours, or even for some days as the case may be. Since I prefer never to use violence, I expect from you in such a case, even more than in any other, your unquestioning obedience. By acting in this way, [[InnocentBystander I shield you from complicity, I absolve you of all responsibility, since I myself make it impossible for you to see what you aren't meant to see]]. [[DealWithTheDevil Do you accept this condition?]]"''
-->''[[CaptainObvious So things happened on board that were quite odd to say the least]], things never to be seen by people not [[AboveGoodAndEvil placing themselves beyond society's laws!]] [[TheReveal Among all the surprises the future had in store for me]], [[MoralEventHorizon this would not be the mildest'']].
* SympathyForTheDevil: [[TheProfessor Professor Aronnax]] is fascinated by WickedCultured Captain Nemo and his creation, [[CoolShip the Nautilus]], for seven months, and he certainly wants to delay the GreatEscape to see more submarine marvels… until he sees Nemo KickTheDog and cross the MoralEventHorizon.
* TechnologyMarchesOn: Electricity was imbued with almost magical power, and a lot of the technological wonders Verne describes seem downright quaint to modern eyes. Still, credit where credit is due, [[ShownTheirWork he did get the fundamentals of how submarines would work in the future essentially right]].
** The ''Nautilus'' was supposed to make 50 knots on Bunsen batteries. [[http://en.wikipedia.org/wiki/Alfa_class_submarine The only modern submarine]] which could approach 50 knots needed 30 000 kW for the main engine. To get 30 000 kW from Bunsen cells their combined size would exceed ''Nautilus'' entire hull in size by a few orders of magnitude.
** Also, an in-universe example of SchizoTech: despite the usual rotating electric motor with brushes being known and used in the 1860s, ''Nautilus'' main engine is an [[http://chestofbooks.com/home-improvement/workshop/Handy-Man/How-To-Make-An-Oscillating-Static-Electric-Motor.html oscillating electric motor]] ([[spoiler: "where large electromagnets actuate a system of levers and gears that transmit the power to the propeller shaft"]]) - less efficient and a royal waste of space.
** The new technology of double hull seemed to solve most problems in an age when most vessels were still wooden sailing ships, so Verne become enthusiastic about ''Nautilus'' double hull able to withstand the pressure "in the deepest ocean trench". No double hulled submarine can go below 1300 meters, specialized deep-diving vehicles are small craft with 5-inch thick shells.
** ''Nautilus'' crew diving suits are [[http://en.wikipedia.org/wiki/First_appearance_of_diving_helmets#The_first_diving_regulators an autonomous version of the heavy helmet of Verne's lifetime]], yet all these had been used only to very shallow depths. To use them hundreds of yards deep with no decompression stops would only make the divers succumb to decompression sickness.
* ThatManIsDead: Whoever Nemo was before he became "The Nameless Avenger", that man is so dead there is no reason to even mention him.
-->''"...I am dead, Professor; as much dead as those of your friends who are sleeping six feet under the earth!"''
* TheseAreThingsManWasNotMeantToKnow: Ned Land's opinion about the beauty of the South Pole’s icebergs (just before the Nautilus will be trapped by them).
--> "It's a wonderful sight! Isn't it, Ned?"
--> "Oh damnation, yes!" Ned Land shot back. "It's superb! I'm furious that I have to admit it. Nobody has ever seen the like. [[ForeShadowing But this sight could cost us dearly]]. And in all honesty, ''I think we're looking at things God never intended for human eyes."''
* TrueCompanions: Captain Nemo claims (and the few interactions Aronnax had with the Nautilus crew never shows us any different) that this is the relationship between the crew:
--> ''.."The Nautilus suffered a collision that cracked one of the engine levers, and it struck this man. My chief officer was standing beside him. This man leaped forward to intercept the blow. A brother lays down his life for his brother, a friend for his friend, what could be simpler? That's the law for everyone on board the Nautilus"''
* {{Ubermensch}} Captain Nemo is an UnbuiltTrope: A WickedCultured WellIntentionedExtremist who claims to be AboveGoodAndEvil because he has done with the society and is practically above any law of the civilized nations thanks to the power of [[CoolShip his submarine, the Nautilus.]] …However, he is a {{Deconstruction}} of the trope, because the contradiction between his unlimited power (that let him cross the MoralEventHorizon) and his compassionate nature causes him a VillainousBreakdown. This dialogue between him and Professor Aronnax lampshade it 14 years before ''Also Sprach Zarathustra'':
--> [[WhatMeasureIsAMook "I have hesitated some time," continued the commander; nothing obliged me to show you hospitality. If I chose to separate myself from you, I should have no interest in seeing you again; I could place you upon the deck of this vessel which has served you as a refuge, I could sink beneath the waters, and forget that you had ever existed. Would not that be my right?"]]
--> [[TheUnfettered "It might be the right of a savage,"]] I answered, [[TheFettered "but not that of a civilized man."]]
--> "Professor," replied the commander, quickly, [[AboveGoodAndEvil "I am not what you call a civilized man! I have done with society entirely, for reasons which I alone have the right of appreciating. I do not, therefore, obey its laws, and I desire you never to allude to them before me again!"]]
--> This was said plainly.[[TheUnfettered A flash of anger and disdain kindled in the eyes of the Unknown, and I had a glimpse of a terrible past in the life of this man]]. [[AboveGoodAndEvil Not only had he put himself beyond the pale of human laws, but he had made himself independent of them, free in the strictest acceptation of the word, quite beyond their reach! Who then would dare to pursue him at the bottom of the sea, when, on its surface, he defied all attempts made against him? What vessel could resist the shock of his submarine monitor? What cuirass, however thick, could withstand the blows of his spur? No man could demand from him an account of his actions; God, if he believed in one -- his conscience, if he had one -- were the sole judges to whom he was answerable]].
* UndyingLoyalty: Exaggerated with Conseil, [[TheProfessor Professor Aronnax's]] servant. He risks his life to save his employer not once, but twice in the novel. When Aronnax talks with Ned Land about the GreatEscape, Conseil considers himself one with his master's decision.
-->''"Your friend Conseil," the fine lad replied serenely, "has nothing to say for himself. He's a completely disinterested party on this question... He's in Master's employ, he thinks like Master, he speaks like Master, and much to his regret, he can't be counted on to form a majority. Only two persons face each other here: Master on one side, Ned Land on the other. That said, your friend Conseil is listening, and he's ready to keep score."''
-->''I couldn't help smiling as Conseil wiped himself out of existence.''
* TheUnreveal:
** Aronnax never discovers Captain Nemo’s true name nor nationality.
** Aronnax writes the last chapter of his book in South Norway. [[JustifiedTrope Any form of Travel between upper Norway and the south is limited]], and thus he still hasn’t discovered what was the nationality of the ship Captain Nemo sank.
** Aronnax faints after he hits his head against the Nautilus, and apparently he never asked Ned and Conseil how they escaped from the Maelstrom.
--> [[CliffhangerCopOut What happened that night, how the skiff escaped from the Maelstrom's fearsome eddies, how Ned Land, Conseil, and I got out of that whirlpool, I'm unable to say. But when I regained consciousness, I was lying in a fisherman's hut on one of the Lofoten Islands. My two companions, safe and sound, were at my bedside clasping my hands. We embraced each other heartily]].
* VillainousBreakdown: Inverted: after Captain Nemo crosses the MoralEventHorizon for the last time, he breaks down not because his plans aren't working but because he is ''not'' AboveGoodAndEvil. [[spoiler: He also could have voluntarily run the Nautilus into The Maelstrom (an enormous whirlpool)]].
* WeaponOfMassDestruction: At the state of technology in 1869, the Nautilus is this: a submarine could easily destroy any ship in the sea without possibility of being persecuted when submerged in the sea. Nemo’s KickTheDog moment shows how terrible its destructive power really is.
* WhamLine: [[spoiler: But by this point observing, studying, and classifying were out of the question.]]
* WhatMeasureIsAMook: Aronnax, Counseil and Ned Land are informed by Captain Nemo that, from his point of view, they are simple mooks and he threatens to invoke this trope. (See {{Ubermensch}}).
* WhereDoesHeGetAllThoseWonderfulToys: Justified. Nautilus was designed by Nemo, all the components ordered from different companies in different countries and shipped by the Nautilus crew to a remote island, where all plans and traces of their shipyard were destroyed after the Nautilus was completed.
* WideEyedIdealist: [[TheProfessor Professor Aronnax]] must be constantly reminded that other people are not as good as himself. He really doesn’t want to believe that Nemo is doing something sinister, and Ned Land must remind him that the war ship that is shooting the Nautilus is doing it ''on purpose''.
* WickedCultured: Nemo isn't quite a villain, but if he were he'd fit the trope. He has a library of 12000 books, ''of which he's read all'', a collection of marine curiosities that would put most museums to shame, an art collection, likewise, and a keen interest in good dining. He also plays a pipe organ.
* WithGreatPowerComesGreatInsanity: The book subtly shows how Captain Nemo is slowly but surely losing his sanity by using the Nautilus as a WeaponOfMassDestruction.
* YourTerroristsAreOurFreedomFighters: Captain Nemo is an early example: he adopts the Ocean as his new homeland and finances the Cretan Rebellion because he hates despots. However, [[CoolShip the Nautilus]] permits him to destroy any of TheEmpire's ships with total impunity (no nation could chase him to the bottom of the sea). His superior technology means that even the military is as helpless as ordinary civilians.
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