[[caption-width-right:350:The main characters of ''Deep Space Nine''.[[note]][[{{Transplant}} Cmr. Worf]], [[BadassBookworm Lt. Jadzia Dax]], [[MrFixIt Chief Miles O'Brien]], [[HospitalHottie Dr. Julian Bashir]], [[TheBartender Quark]], [[BaldBlackLeaderGuy Cpn. Benjamin Sisko]], [[VoluntaryShapeshifting Constable Odo]], [[ActionGirl Major Kira Nerys]], and [[IntrepidReporter Jake Sisko]].[[/note]] Not pictured: [[LoadsAndLoadsOfCharacters Ezri, Nog, Rom, Leeta, Garak, Dukat, Winn, Bareil, Keiko, Molly, Damar, Weyoun, Gowron, Martok, Ziyal, Morn...]]]]

->''"Think of it: Five years ago, no one had ever heard of Bajor or Deep Space Nine. And now all our hopes rest here."''
-->-- '''Chancellor Gowron'''

''Star Trek: Deep Space Nine'' is the second of the "next generation" of ''Franchise/StarTrek'' shows, airing after ''[[Series/StarTrekTheNextGeneration The Next Generation]]'' for two years, then alternating with UPN's ''[[Series/StarTrekVoyager Voyager]]'' for the remaining five years. Set on an orbital {{space station}}, [=DS9=] traded the WagonTrainToTheStars premise for "[[SpaceWestern Fort Apache in Space]]". Ira Behr, the head writer, cited ''Series/TheRifleman'' as another influence (particularly the [[PapaWolf father-son]] dynamic).

[[Recap/StarTrekTheNextGenerationS6E10ChainOfCommand When we last left Next Gen]], the remote world of Bajor had just booted out its [[WeWilluseManualLaborInTheFuture occupiers]] through a war of attrition and a fair amount of terrorism. With the planet spiraling into anarchy, Starfleet sent a detachment of officers lead by Commander Sisko as a diplomatic liaison and provide aid to the Bajorans. They take up residence at a Cardassian station called Terok Nor, [[MeaningfulRename rechristened]] Deep Space 9 as a makeshift Starfleet outpost. In the pilot, a one-of-a-kind stable [[OurWormholesAreDifferent wormhole]] is discovered, leading to a distant and uncharted section of the galaxy. Instantly, Bajor is transformed from a [[NothingExcitingEverHappensHere rustic backwater]] into the most valuable piece of real estate in the quadrant, and [=DS9=] is assigned to monitor the wormhole's traffic. The appearance of the wormhole is seen by the Bajorans as fulfilling a religious prophecy and Sisko is declared to be "[[TheChosenOne The Emissary]]." The fixed base allowed the show to delve deeply into the politics of the established ''Star Trek'' universe, but the appearance of the wormhole also caught the attention of the Dominion, a [[TheEmpire less cuddly]] counterpart to the United Federation of Planets.

What made ''[=DS9=]'' so unusual in Trekdom was that every action had consequences. Part of it is the writers becoming more comfortable altering Creator/GeneRoddenberry's spotless, optimistic future: nobody on Bajor particularly got along with each other and, unlike the ship-based series, the crew couldn't just '[[ButNowIMustGo jump to warp]]' and leave the Problem of the Week behind. The writers employed {{Story Arc}}s much more extensively than in other ''Treks'' (including a full MythArc dealing with the Dominion), showing it had now earned the "SpaceOpera" genre tag that it had been given. Perhaps most importantly, by shifting focus from TNG's bold explorers to [=DS9's=] [[JoinTheArmyTheySaid overworked jarheads]], the writers were able to scrutinize the Federation as it appears to outsiders: a noble organization which still has problems with bureaucracy and some [[UtopiaJustifiesTheMeans skeletons in its closet]].

While all ''Trek'' shows have large casts, [=DS9=] is the only one which qualifies for LoadsAndLoadsOfCharacters, by virtue of having a fixed location and a population surrounding it. Consequently, the show was overrun with {{Fake Guest Star}}s, Aron Eisenberg (Nog), Max Grodenchik (Rom) and Andrew Robinson (Garak) standing out in particular; all three characters appeared within the show's first two episodes and were heavily featured straight through to the series finale. This was a show that could do a BottleEpisode but have it star people who weren't even in the opening credits; [[Recap/StarTrekDeepSpaceNineS07E10ItsOnlyAPaperMoon one]] focused on Nog's recovery from a war injury with the help of a second recurring guest, and [[Recap/StarTrekDeepSpaceNineS06E12WhoMournsForMorn another]] on the disappearance of an AscendedExtra who [[TheVoiceless never once had a line]]!

As a result of this kind of thing, the show tends to [[BrokenBase divide Trekkies quite a bit]]: people who like ''Trek'' for the [[AnAesop morality plays]] and spacefaring action may be turned off by the [[{{Soaperizing}} soapy melodrama]] and [[{{Deconstruction}} deconstruction]] of Roddenberry's utopian theme. On the other hand, those who ''do'' like [=DS9=] tend to ('''heavily''') prefer it over other ''Trek'' shows, forming a little subculture of their own in Trekkie fandom known as "Niners".

''Deep Space Nine'' is very frequently compared to ''Series/BabylonFive'', the ''[[DuelingWorks other]]'' 90's cult SpaceOpera show set on a space station, incorporating matters of faith, focusing on conflicts between interstellar empires, having LoadsAndLoadsOfCharacters (aided, in ''B5''[='s=] case, by a lot of CastTurnover), featuring strong {{Myth Arc}}s, and {{deconstructing}} the future. Indeed, there were frequent accusations that the two shows had ripped one another off; Creator/JMichaelStraczynski has implied that {{Creator/Paramount}} effectively stole an idea that he pitched to them and [[DolledUpInstallment stuck a Star Trek brand]] on it. Although [=DS9=]'s and [=B5=]'s pilots are similar, Season Four was the point at which the two began to dovetail.

The show currently runs in... [[GermansLoveDavidHasselhoff British and Japanese TV]]. It used to run in Syndication on Creator/SpikeTV in the United States, but due to low ratings has not aired for some time. As of October 2011 the complete series is available on {{Creator/Netflix}} streaming in the United States (where, by many reports, it has been far more popular than it was in rerun broadcast and is a staple of the service). For that matter, it is also on Amazon Instant Video, Hulu and CBS All Access as well, so basically you're covered if you're signed up on any of these. Alongside all the other ''Trek'' shows and films, ''[=DS9=]'' was made available in its entirety in Netflix Europe in 2016.

In 2017, Ira Steven Behr and Adam Nimoy announced they were crowdfunding a documentary on the series, ''[[https://ds9documentary.com/about/ What We Left Behind: Looking Back at Star Trek: Deep Space Nine]]''. In addition to bringing back most of the major actors, the film is to look at ''[=DS9=]'''s cultural impact, particularly its post-wrap rise in popularity in syndication and streaming, and will feature Behr getting his writers' room together to plot a "what if" season 8.

In spite of the obvious limitations of singling out episodes in a heavily [[ContinuityLockOut arc-based series]], this show has a tool for voting on [[http://tvtropes.org/pmwiki/crowner.php/BestEpisode/StarTrekDeepSpaceNine Favorite Episodes]].

Related works in the Franchise/StarTrekExpandedUniverse include the ''Literature/TerokNor'' trilogy, a sub-series of ''Literature/StarTrekTheLostEra'' which chronicles the Occupation of Bajor and features many of the Bajoran and Cardassian characters, and the ''Literature/StarTrekDeepSpaceNineRelaunch'' continuation series.
!!This series provides examples of the following tropes:

* StarTrekDeepSpaceNine/TropesAToD
* StarTrekDeepSpaceNine/TropesEToL
* StarTrekDeepSpaceNine/TropesMToP
* StarTrekDeepSpaceNine/TropesQToZ