''Tranquilium'' (''Транквилиум'') is a 1996 Speculative Fiction (see immediately below) novel by Russian writer Andrey Lazarchuk.

The genre is difficult to define beyond Speculative Fiction. It has elements of historical fiction and political thriller and conspiracy literature; it eventually verges on being a CosmicHorrorStory; and it may be considered with equal validity as science fiction with ImportedAlienPhlebotinum or as fantasy with MagicAIsMagicA. The setting is, at the first glance, a generally Earth-like AnotherDimension (the eponymous Tranquilium) that is somehow connected with [[{{Mordor}} a ruined shadow world]] and through it with our Earth; in fact it's revealed rather quickly that Tranquilium was originally settled by colonists from Earth, which partly explains why the two nations that share much of the known world Merryland and Palladia [[FantasyCounterpartCulture are so similar]] to Victorian Britain/America and Imperial Russia, respectively. It is generally assumed in Tranquilium that all contact with the Old World was lost long ago; in truth some people from the Old World still can and do cross over to Tranquilium, for various purposes and some other people really don't want them to, for a variety of reasons (but mostly because they want to take over), setting up the initial conflict, which gets [[GambitPileup much more convoluted]] as the plot develops.

The story begins in [[ColdWar 1983]] in the coastal Merryland town of Port Elizabeth. Gleb Marin, the 18-year-old son of a famous Palladian cartographer and public figure who recently died under mysterious circumstances, arrives to the town after having successfully graduated from an elite school and goes to the beach to think his situation over, only to end up rescuing [[OfficerAndAGentleman Captain-Inspector]] Cyrus Campbell, Lord Stableford, who had almost drowned after being thrown overboard by mutineers on a ship. This rescue gets him noticed by [[ColonelBadass Colonel Williams]], a resident ReasonableAuthorityFigure who apparently knew his father and who advises Gleb to visit the man he saved. Becoming a guest at the Stableford manor, Gleb gets acquainted with Lord Stableford's Palladian wife, Lady Svetlana, and her friend [[LadyOfAdventure Olive Nolan]].

Meanwhile, the original mutiny ends up turning into a full-blown rebellion apparently orchestrated by a strange and dangerous group known only as the [[{{KGB}} "cayjibbers"]], the town is engulfed by combat and the lives of all the main characters repeatedly come into danger. Parallel to this it is revealed that Gleb can go into the aforementioned shadow world which somehow corresponds to Tranquilium, an ability he uses to help the militia combat the rebels; while in the shadow world, he encounters a strange man in the otherwise unpopulated dimension, equipped with hi-tech (read: 1980s Earth) weapons. Upon surviving the uprising, Gleb, Cyrus, Svetlana and Olive decide that their meeting was preordained by fate, and forge a special bond, swearing to meet again under similar circumstances; they are later joined in this by Colonel Williams, who also brings Gleb into the already mentioned main conflict in the setting, a secret war between the Forbidders based in Palladia and Merryland and the KGB, which apparently seeks to conquer the nations of Tranquilium for [[TheEmpire the Soviet Union]] and/or [[UtopiaJustifiesTheMeans bring them the benefits of modern civilisation, whether they like it or not]]. Gleb's apparently unique ability - slipping effortlessly into the shadow world and his father's legacy make him an obvious target in this war, and so he is forced to go into hiding to evade KGB agents and their allies, while also having a love affair with Svetlana.

And that's just the beginning of the first part out of three. By the end, just about nothing is the same, both in [[NothingIsTheSameAnymore the reality of the setting]] and in what the reader knows about it ([[MindScrew inasmuch as one could know anything about it]]), [[BreakTheCutie to say nothing of]] [[CharacterDevelopment the four or five main characters]], [[TraumaCongaLine who pretty much all go through hell]] [[spoiler:and survive, but [[TheWoobie not without lots and lots of scars]]]].

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!!Provides Examples Of:

* AbsenceMakesTheHeartGoYonder: Strange version, as [[spoiler: Gleb's absence leads to Svetlana falling in love... with Cyrus, her husband]].
* ActionMom: In the beginning of Part Three, Billy thinks his mother is this and fantasises about her slaughtering his most hated teacher at school. [[spoiler: He isn't that off about the first part, though ultimately she's only as actiony as she has to be in the circumstances]].
* AFatherToHisMen: Cyrus, as seen when he becomes admiral. Also, [[spoiler: Gleb, especially after he becomes the Tsar of Palladia]]. In the latter case it's at least partly GenreSavvy, though not really insincere.
* AgentMulder: Not during the events of the book itself, but it is mentioned that [[spoiler: Colonel Williams']] backstory is pretty much this to a tee, as he used to be an FBI agent who was repeatedly ignored by his higher-ups while investigating various weird events connected with Tranquilium and Soviet efforts to infiltrate it, until finally quitting in disgust, going native and resolving to fight a one-man war against the Soviets if need be.
* AwakeningTheSleepingGiant: Sorta happens in Part Three. It's not that Gleb wasn't busy with his own subtle plans, but he was [[OrcusOnHisThrone seemingly inactive]] until [[spoiler: the Americans]] decided to kidnap his son to make either of them do their bidding. Cue CurbStompBattle.
* ColdBloodedTorture: Colonel Williams' men do not joke around. There is a graphic description of them literally torturing a key Soviet informer to death, but not before he exposed over a hundred agents. The Soviets for their part torture Gleb, but it's more subtle mental torture designed to break his spirit in hopes of recruiting him due to his unique abilities.
* ColonelBadass: Colonel Williams, ofcourse. This particularly shines through at Port Elizabeth and during his querrila-esque raids against KGB infiltrators, not to mention [[spoiler: the shadow world campaign in the middle of Part Two, which was to be a literal suicide mission for him and his squad and which singlehandedly thwarted the Soviet invasion plans]]. He's a hella ruthless and efficient antihero.
* ComesGreatResponsibility: Gleb certainly takes [[spoiler: controlling Tranquilium and guiding its destiny]] seriously, though his interpretation is evidently different from what [[spoiler: the Atlanteans]] originally intended.
* {{Cult}}: The Ahrimanites, or so they seem until Part Three.
* DaddysGirl: Svetlana.
* FanOfThePast: The culture of Tranquilium revolves around this towards 19th century Earth, which is why the Americans who founded Merryland are so insistent on making it like VictorianBritain. This cultural complex is rather disturbing to some of the more intellectual characters, who think that Tranquilium needs to develop a self-sufficient culture. [[spoiler: Gleb's plan at the end is apparently supposed to bring about just that, though how successful it would be is hard to say.]]
* FantasyCounterpartCulture: It's explained early on that there is a reason why Merryland and Palladia are so similar to 19th century Earth Britain and Russia; they were, after all, originally settled by people that came from Earth in the 18th-19th centuries.
* GovernmentConspiracy: The higher-ups in Palladian and Merryland governments are in one (the Palladians rather more so, with many key government figures being part of the Palladian Forbidder Circle, while members of the Merryland League of Forbidders are more like Almighty Janitors).
* HiddenAgendaVillain: [[PathOfInspiration The Ahrimanites]], sorta; they are definitely out there and are considered one of the main players by those in the know, but for the first two parts they almost entirely remain in the background of the plot, and nobody quite knows what are they doing or why. Their leader, one Volkert, counts as a HiddenVillain (and is eventually revealed to be [[spoiler: a high-ranking American agent]]).
* LadyOfAdventure: Olive is this to a tee ([[spoiler: or ''was'', before she got ''broken'' into a BrokenBird MysteriousWaif]]).
* MamaBear: Svetlana, after giving birth to Billy in the beginning of Part Two.
* TheMenInBlack: The Forbidders; their priority seems to be combating the KGB, but they are very insistent on preventing or minimising all Earth influence on Tranquilium in general.
* NiceJobFixingItVillain: the Soviet meddling on Tranquilium, which was supposed to be an asymmetric Cold War strategy (conquering a world to evacuate the most important people there once a nuclear war begins on Earth), has led to Merryland [[spoiler: undergoing a revolution]] and Palladia [[spoiler: being put on the defense in a major war]]. All good and fine, but the weird connection between events on Earth and on Tranquilium means that all this resulted in America's general upsurge and the Soviet Union's pre-collapse stagnation, respectively! Subverted in that [[spoiler: the Americans are villains too, after a fashion, and they have been manipulating the Soviets into fixing things for them]].
* OceanPunk: A mild example early on, but still, all the landmasses in ''Tranquilium'' are basically islands of various sizes, and even the supposedly "land-oriented" Merryland is based on a very large island ("the Island", in fact) where most of the major settlements are coastal. Ofcourse, at the end [[spoiler: it becomes a classic example of this trope, as [[NiceJobBreakingItHero Gleb's plans to severe all existing connections between Tranquilium and the Earth also stopped the circulation of waters between the Earth and Tranquilium, which led to most of his world's landmass being gradually submerged]]. Thankfully, he figured this out in time and focused his efforts from the end of Part Two onwards on arranging a reasonably comfortable transition to a classical OceanPunk culture, constructing huge, hi-tech Arcs along with other cool ships and airships to evacuate the population to heretofore unexplored regions]].
* OutGambitted: The later villains tend to have this happen to them when they mess with Gleb, due to his acquired (apparent) nigh-omniscience and understanding of how Tranquilium works. Part Three is a particularly impressive example of this, when it turns out that [[spoiler: the Americans]], who have previously outgambitted the Soviets, have now been outgambitted by Gleb and his allies (and hell, even then their gambit in Part Three was a desperate ploy after Gleb screwed over all their plans that the Soviets were playing into in the end of Part Two, though he hardly even noticed ''them'' among all the other people eager to control the world).
* ParentalAbandonment: Gleb's father is dead and his mother [[spoiler: is in an insane asylum]], so she might as well be [[MissingMom gone]] as well. [[spoiler: Svetlana's father]] eventually dies as well. And at the beginning of the third chapter, Billy doesn't know about his biological father, [[DisappearedDad while the man he thinks is his father is a prisoner of war]].
* PathOfInspiration: The Ahrimanites are eventually revealed to be this, being a cover for [[spoiler: American intelligence on Tranquilium. Because did you really think they would've just ignored Soviet plans to conquer an AlternateDimension in the middle of the ColdWar?]]
* TheRevolutionWillNotBeVilified: Subverted: the revolutionaries in Merryland ([[spoiler: and, to a much lesser extent, in Palladia, since those are a whole different bunch]]) ''are'' the antagonists, being puppets of the KGB. Their leaders are [[WellIntentionedExtremist Well Intentioned Extremists]] ''at best''. And as for their actions, TheRevolutionWillNotBeCivilized hardly begins to cover it. [[spoiler: After they succeed, their actions seem almost entirely based on a combination of the worst aspects of the Jacobins and the Bolsheviks at the heyday of their respective reigns of terror]].
* SecretLegacy: Gleb has one, connected to [[spoiler: the metaphysical mechanics of controlling and maintaining Tranquilium, and so also to the legacy of the Atlanteans who made it in the first place and created this semi-hereditary position]]. His discovery and eventual mastery of this legacy is one of the main plot threads. The same trope applies to his son, by the way, though he is forced to discover it rather earlier (in Part Three).
* TheManBehindTheMan: Successive Soviet project leaders (most notably, Chemdalov) and Parvis are this to the various Labour leaders in Merryland (Carrigan, Doherty, Macned).
* TurnOutLikeHisFather: It is brought up early on that Gleb Marin certainly does take after his father Boris in some regards, even putting aside the, uh, [[SecretLegacy family secret]] that apparently influences everyone in turn. Arguably this also goes for Gleb's son Billy.
* UnwittingPawn: The Soviets, to [[spoiler: the Americans, who were perfectly content to let them run around trying to take over Tranquilium by political and military means while they used the weird metaphysical/historical connections between Tranquilium and Earth to throw the USSR into stagnation and pull USA ahead]]. Also, the old Merryland government to the KGB; Chemdalov, one of the early Soviet antagonists, commented that President Hawke is smart, but way too stubborn and will one way or another play into their hands.
* YouCantThwartStageOne: On one hand, seemingly averted when Colonel Williams DOES thwart what is literally Stage One of the enemy plan, which is the uprising in Port Elizabeth; on the other hand, played straight since the KGB does have back-up plans, and even [[spoiler: killing Andropov]] isn't enough to stop them from [[spoiler: launching a revolution in Merryland and thus, paving the way for a full-scale military invasion of Tranquilium]] at the end of Part One.
* YourCheatingHeart: The affair between Gleb and Svetlana. Subverted in that [[spoiler: her husband knows and doesn't mind, as they were planning to get divorced anyway, and were just putting it off to avoid scandal; taken further when, after being separated from Gleb, she reunites with her genuinely loving husband and doesn't resume the affair even when Gleb shows up again]].
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