[[quoteright:300:https://static.tvtropes.org/pmwiki/pub/images/ds_duo_5085.jpg]]
[[caption-width-right:300:Their lives aren't the same anymore in Hirasaki City.]]

''Shin Megami Tensei: Devil Summoner'' is a turn-based RPG originally released for the Platform/SegaSaturn on December 20, 1995, and the first game in the ''Devil Summoner'' sub-series. In fact, it was the first game from the entire [[Franchise/ShinMegamiTensei Megami Tensei]] franchise to be released for the Saturn, and it has been re-released several times since then, with the first being for the Platform/PlaystationPortable on December 20, 2005, and the latest one being for the Japanese-based Playstation Network in 2010. A live-action [=TV=] adaptation was aired in Japan in the early 2000s with 25 episodes, being initially based loosely on the game, but diverging halfway through with some original stuff thrown in that makes it a bit different from the original source in the second season.

The game is followed up (in terms of the canon timeline) by ''[[VideoGame/SoulHackers Devil Summoner: Soul Hackers]]''. Two prequel games, ''[[VideoGame/RaidouKuzunohaVsTheSoullessArmy Devil Summoner: Raidou Kuzunoha vs. The Soulless Army]]'' and ''[[VideoGame/RaidouKuzunohaVsKingAbaddon Devil Summoner: Raidou Kuzunoha vs. King Abaddon]]'', explore the origins of the Kuzunoha clan and how they were involved in fighting against hostile demons in a post-Meiji Revolution Japan.

The story of ''Devil Summoner'' takes place in Hirasaki City in the mid-1990s. You play a normal university student who's living out an ordinary life in the city... That is until he gets reports on the local news that there are witnesses who had reported to the police about sightings of mysterious demons prowling around the city. The city's police force are also in trouble since they are now investigating cases that cannot be solved since the only perpetrators responsible for them are not human. But never mind that now. The student's girlfriend, Kumiko Hatano, informs him that she needs to borrow a book written by Professor Azuma at the city's library in order to read up on his studies regarding the dark past of Japan prior to the 20th Century. After doing a few errands, the students is ambushed by demons and is saved by anti-demon detective Kyouji Kuzunoha and his partner, Rei Reiho.

Despite this event, Kyouji is assassinated under unknown circumstances. Later on, the student is also hunted down and assassinated by a man named Sid Davis, who wants the book Kumiko has borrowed from the library. While his soul was supposed to be transported through the River Styx, Charon informs him that he needs to get back to the real world. Thus, the adventure begins when the student's soul gets planted into Kyouji's body. Together with Rei, they work together to hunt down Sid and eliminate the demons prowling in the city. Along the way, Kumiko gets kidnapped thanks to Sid, and the duo later learns that the city has a dark past tying back to the early history of Japan which explains why Kumiko was abducted to begin with.

Like in the mainstream ''Shin Megami Tensei'' games, the core mechanic of recruiting and using demons to fight alongside the player is retained. This involves giving appropriate answers or handing out money and macca to any kind of demon before it joins your ranks. Sometimes it doesn't work due to either their personality or due to the presence of a full moon. Quests are given by the various residents of Hirasaki City due to Kyouji's reputation as an anti-demon detective; most of them advance the story, while some allow the player and the demons to earn experience, money and macca. Demon fusion is also retained, allowing the players to create any kind of demon with specific strengths/weaknesses and skills.

For now, the game is the only one in the ''Devil Summoner'' franchise to not have an official release outside of Asia. Atlus did attempt to promote the game for an international release at one point, but they later decided to stop promoting it outside of Japan. There's also a novel adaptation known as ''Shin Megami Tensei: Devil Summoner - Sealed Soul''. A novel side story ''Shin Megami Tensei: Devil Summoner Side Story - Lamentations of a Requiem'' centers on Inaruna's past.

As of 2021, there's an attempt to [[https://iwakuraproductions.wordpress.com/2021/01/27/shin-megami-tensei-devil-summoner-fan-translation-preview-colons/ get the game an English fan translation]]. Likewise, efforts are made to translate the live-action drama version.

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!!''Devil Summoner'' provides examples of:

* AlternateTimeline: To the one seen in ''VideoGame/ShinMegamiTenseiI'' and ''VideoGame/ShinMegamiTenseiII'', with some crucial differences described below in MythologyGag.
* BittersweetEnding: [[spoiler:Even though the new Kyouji and Rei defeated Inaruna and Sid to save Hirasaki City from a disaster, the former noted that he can't return to his original body since he's stuck in Kyouji's body forever. The "other" Kyouji has to jump from body to body in order to survive. Kumiko can't reunite with the protagonist since he's stuck in Kyouji's body.]]
* BossAlteringConsequence: The Orgone Ghost in Toa TV Station's radio tower becomes weaker if you defeat its servants, [[WolfpackBoss Julia, Speedy, and Mikiya]] in an optional boss fight in the station proper. The weakened version has lower stats but gains the ability to use Swing Thunder and Rest in addition to its regular skillset.
* ChanceMeetingBetweenAntagonists: How the protagonist and Sid first meet in Hirasaki City, until the latter bluntly tells the former that he'll kill him for not having the book with him.
* EarlyInstallmentCharacterDesignDifference: Devil Summoner introduces the more familiar designs for almost all returning demons along with being the first game that introduced Kazuma Kaneko's more [[ArtEvolution iconic style]], but several demons have different color schemes or slight differences in their designs compared to future games (like Slime, Moh Shuuvu, and Succubus). Handful of other demons (like Pixie) [[YouDontLookLikeYou have completely different designs]] unique to this game. Soul Hackers would introduce most demon's well known color schemes while still having a few unique designs exclusive to it that fits with that game's Cyberpunk theming. ''[[{{VideoGame/ShinMegamiTenseiIIINocturne}} Shin Megami Tensei III: Nocturne]]'' introduces the standard design for these demons, which appear in all future mainline games along with ''{{Franchise/Persona}}'' (with a handful of exceptions).
* GrandTheftMe: [[spoiler:Kyouji attempts this on the protagonist after they go to Hell to get back into his body, but it fails because his soul has been away from the body too long.]]
* JesusTaboo: While the name is avoided, this game is nevertheless the sole aversion of this trope in the franchise. The demon Agony, who is exclusive to this game and the ''Card Summoner'' spinoff, is a blatant reference to Christ's Passion and shows the man himself carrying his cross.
* MythologyGag: Gotou and Thorman from ''[[VideoGame/ShinMegamiTenseiI'' are mentioned in news reports throughout the game. This time, Gotou was arrested by [=JGSDF=] military police officers for attempting to create an arsenal of small arms from the [=JGSDF=] in order to launch a revolt. The police don't know if he needs psychiatric attention since Gotou's fellow [=JGSDF=] officers mentioned in the news that he was acting very unusual prior to his arrest. Meanwhile, Thorman died of a heart attack and was noted for fostering good relations between Japan and the US as American ambassador to Japan.
** In the novel ''Shin Megami Tensei: Devil Summoner - Sealed Soul'', the protagonist works with a demon known as Cerberus.
* PlotTriggeringBook: The book the protagonist checks at the start of the game, "Theory on Ancient Japanese Civilization" for their girlfriend results in the protagonist's and their girlfriend's death which leads to the rest of the plot.
* PoliceAreUseless: The city's local police force can't seem to get a grip on who is responsible for a sudden rash of criminal incidents since they cannot find human culprits. [[spoiler:It gets worse when the detectives learn that Chief Atsushi Nakagomi is Kumbhanda, a mole (and a demon) working on behalf of Sid.]]
* SequentialBoss: Sid Davis and the FinalBoss's two forms are fought back to back.
* SkippableBoss: East Asia TV and the Radio Tower are two connected dungeons. East Asia TV is set up such that you can completely ignore the boss fight there, but doing this will make the boss in the Radio Tower stronger.
* SmallRoleBigImpact: Thormann and Gotou from ''VideoGame/ShinMegamiTenseiI'' are only mentioned in news reports as now being out of commission. The impact on this particular Megaten timeline is ''huge'' however, as the two can no longer rally the various forces of law and chaos to trigger the apocalypse that leads to the events of the first and second mainline ''SMT'' games. It also shows what ''VideoGame/ShinMegamiTenseiIf'' meant by the events of the first ''SMT'' not happening, and the game's protagonist Tamaki as well as Kyouji would later go on to star in the massive ''Persona'' spin off franchise. The events of ''Raidou Kuzunoha'' would further give context on the timeline shift.
* SplitPersonalityTakeover: A literal one since the "old" Kyouji is forced to use another body in order to live while the student uses Kyouji's own body.
* StealingTheCredit: Unwitting example -- one of the many drawbacks of your soul being stuck in someone else's body is that ''they'' get the credit for ''your'' work.
* SwordAndGun: How Kyouji and Rei fight against hostile demons aside from magic and siccing their own demons against them.
* UnholyGround: The city itself whenever parts of it gets distorted by the Alien Dimension thanks to Sid.
* UrbanFantasy: Is one set in modern times away from the mainstream ''Megami Tensei'' games, next to the Persona games.