Made in 1994, ''Blue Seed'' is (loosely) based on the Izumo cycle of Japanese mythology and the tale of the god Susanoo and the eight-headed monster Yamata no {{Orochi}}. The original manga was written by Yuzo Takada and was made into a 26 episode anime series.

Momiji Fujimiya, a normal middle school girl, is one day stopped on her way to school by a cat eyed man with greenish hair and magatama beads (read: blue seeds) who calls her "Kushinada" and then tries to kill her. Momiji is saved by the sudden appearance of two government officials, one of whom shoots the man in the arm and sends him fleeing.

Momiji is intrigued as to why she was referred to as "Kushinada". She discovers that "Kushinada" refers to an ancient princess whose blood holds the power to stop the ancient monsters known as Aragami by sending them to an eternal sleep. Momiji dismisses the idea that she could be such a person, despite the fact she lives with her mother and grandmother in a shrine in Izumo. However, she soon changes her mind after vines begin to appear from every crack and opening attempting to capture her as they whisper "Kushinada".

Momiji tries to escape, not knowing that the vines are being employed by a powerful Aragami known as Orochi. Fortunately, she is saved by the man with the magatamas embedded into his hands, who introduces himself as Mamoru Kusanagi. He confronts Orochi using Momiji as bait. The plan fails and the government officials appear again. They reveal themselves to be members of the Terrestrial Administration Center (TAC for short), and manage to subdue Orochi. However, with the last of its strength, it makes a final attempt on Kusanagi.

Momiji saves Kusanagi by taking Orochi's blow. Impaled by the Aragami, instead of dying, she is instead fused with the magatama, more specifically identified as a mitama, which gives Momiji the ability to sense the presence of other Aragami. The TAC agents explain that they are an organization dedicated to defeating the Aragami, who seek to destroy humanity. The current Kushinada, Momiji, must aid them because the other Kushinada, Momiji's twin sister, is thought to be dead. Momiji, wishing to discover more about the twin sister she never knew and also to fulfill her destiny, agrees to join the TAC under the protection of Kusanagi, who wishes to destroy his former masters, the Aragami.

The story becomes increasingly complex with the appearance of Murakumo, a man with eight mitamas who kills any Aragami he comes across for his own personal reasons. Kusanagi repeatedly attempts to kill Murakumo. Then Momiji's twin Kaede reappears along with a strange energy field in Tokyo, and Murakumo and Kaede's plans soon become clear - they intend to resurrect the god Susano-oh and purify the world of humanity's influences, with Kaede acting as the leader of the movement.

There is also a three episode {{OVA}}, ''Blue Seed Beyond'', which takes place [[{{Timeskip}} two years after]] the end of the TV series. It concerns what seems to be a resurgence of aragami ([[spoiler:actually created via biotechnology]]), and introduces a new character, Valencia Tachibana. Like Kusanagi, she was implanted with a mitama without turning into a full aragami.
%comment% That last paragraph was copied to http://en.wikipedia.org/wiki/Blue_Seed#Plot 2010-02-15.

Also has nothing to do with the "sour, yet refreshing" spice from the ''VideoGame/LostInBlue'' games.

!!This show provides examples of:

* AbortedDeclarationOfLove: Ryoko to Kunikida. "I love... Japan."
* ActionGirl:
** Koume and Sakura.
** Valencia in the {{OVA}}.
* AdaptationExpansion: Whereas many anime OvertookTheManga, the manga for Blue Seed was only two volumes, so the anime added some episodes [[CharacterFocus focusing on the characters]]. The fact that there were also Aragami attacks kept these from being outright {{Filler}}.
* AlienBlood: Aragami and half-aragami have green blood.
* {{Anticlimax}}: In the {{OVA}}, [[spoiler:the BigBad goes down with a few gunshots, despite looking a lot tougher than that.]]
* ApocalypseMaiden: [[spoiler:Kaede, after her FaceHeelTurn.]]
* {{Atlantis}}: An odd example; in this setting, the Japanese archipelago was all but uninhabitable several thousand years ago, and the first inhabitants created the Arigami to all but {{Terraform}} the place. Their current rampages are thus as much a ZerothLawRebellion as GaiasVengeance.
* AttackItsWeakPoint: As Aragami are only tiny little seeds possessing host bodies, the seeds have to be destroyed in order to actually kill the thing for good.
* AttackOfThe50FootWhatever: Aragami tend to make giant versions of their host for their attacks. This includes insects, a GiantSpider, mutated trees, jellyfish and more.
* BadassDriver: Matsudaira in the OVA. She pulls some stunt driving moves in San Francisco that terrify Sugishita and throw Koume around in the back seat.
* BarbieDollAnatomy: Averted as part of the {{OVA}}'s fanservice.
* BarrierMaiden: Kaede and Momiji.
* BedsheetLadder: Momiji uses one in episode 3 when she thinks she needs to make a break for it from Kunikida's place.
* BigOlEyebrows: Used... interestingly. Rather than give Kusanagi bushy eyebrows, he ends up with '''four''' normalish ones. This is {{lampshaded}} in an {{omake}}.
%%* BladeBelowTheShoulder
* BodyguardCrush: Momiji on Kusanagi.
* BookEnds: The first and final omakes end with the same scene: Momiji blasting the heck out of Kusanagi and Kunikida.
* BrickJoke: The first omake has Kunikida buying sexy pictures of the TAC girls from Kusanagi, with the ones of Momiji still being developed. Then Momiji shoots them with a machine gun. In the thirteenth and final omake, those photos are finally developed and seen just before Momiji again shoots them with a machine gun.
* BringMyRedJacket: Kusanagi, though the blood thing doesn't fit so much, since his is [[AlienBlood green]].
* BrokenBird: [[spoiler:Kaede. She apparently had her FaceHeelTurn because the TAC used her abilities but never saw her as a person. Specially her adoptive father, Kunikida.]]
** Momiji actually averted becoming this, via calling the TAC out on this in the third episode when they tried to do it to her. That time around, they listened and made her a full-fledged member.
* ButNotTooForeign: Yamazaki Sakura, Japanese but raised in America after her mother died.
* ChivalrousPervert: Kusanagi
* ClothingDamage: [[LampshadeHanging Lampshaded]] in an Omake Theater, as to where Kusanagi gets all of his red coats that are constantly being torn up.
* CulturalTranslation: The CreatureHunterOrganization would be more appropriately translated as the "National Land Management Bureau" or NLMB - the group's InUniverse reputation is a bunch of paper pushers, and the {{Masquerade}} keeps most from knowing about the Arigami until the final story arc. However, Western audiences expect a group of [[WhoYouGonnaCall monster hunters]] to have an appropriately grandiose name, hence their official title of "Terrestrial Administration Center" or TAC.
* CombatTentacles: Many of the aragami have these.
* ConspicuouslyLightPatch: Lampshaded in episode 3 of Omake Theatre. "The background was drawn on an animation cel! How many anime characters have died because they failed to recognize it?"
* CoolOldLady: In episode 12 of Omake Theatre, Momiji's grandma goes ''clubbing''.
* CuteClumsyGirl: Momiji
* DangerouslyShortSkirt: In the OAV, Sugishita impose a highly impractical uniform on the female members of the TAC
* DayInTheLimelight: Each TAC member gets an episode, usually for CharacterDevelopment.
* DisappearedDad: Momiji's father is never shown nor mentioned throughout the entire series.
* DowntimeDowngrade: [[spoiler: Subplot of the Blue Seed 2 OVA series epilogue. In the opening of the first episode Momiji and Kusanagi's relationship is heavily on the rocks, with Momiji outwardly worrying that Kusanagi will break up with her. She even tries to ''sleep'' with him at one point and he rejects her, calling her a kid. The rest of the OVA deals with the subplot of Kusanagi trying to deal with the fact that his body could be dangerous for Momiji, should they become more intimate. At the end of the second episode of the OVA it's clear that while Kusanagi will continue to date Momiji, and that they definitely love each other, the relationship itself is still in shaky ground. However it's shown that both are growing to overcome this, so the trope is Downplayed.]]
** [[spoiler:Koume and Yaegashi also suffered this, but the two reconcile and even make plans to get engaged by the end of the second episode.]]
%% ExcitedEpisodeTitle: All but two titles. (please quote one)
* EverybodyIsSingle: At the start of the series
* EvilTwin: Kaede to Momiji.
* FanService:
** How many times we've seen [[PantyShot Momiji's panties]]?
** And then there is [[SkinshipGrope Sakura groping Momiji's breasts]] in ''Beyond'', just to admire how much they'd grown.
** [[MsFanservice Valencia provides a]] ''lot'' of fanservice all on her own.
* GagDub: The monster movie omake, at least in the English version, was a take on old, poorly-dubbed kaiju films.
* {{Gainaxing}}: Namely in ''Beyond''.
* GodivaHair: [[spoiler:Sakura's mom.]]
* GoofyPrintUnderwear: A running gag involves Momiji displaying a different animal on the seat of her underwear when she does her PantyShot. The other characters maintain a betting pool on just what's going to show up on her panties any given day.
* GratuitousEnglish: See entry for ButNotTooForeign, above. The shift in Sakura's pronunciation from "Mommy" (American) back to "Mama" (Japanese--Engrish, but still Japanese) actually marks an important turning point in one episode.
* GreenAesop
* HeadDesk: Done twice by Momiji by accident in episodes 3 and 4 as a result of bowing too deeply. The first time is on an actual desk, the second on the barrel of a bazooka where she knocks herself silly.
* HellishPupils:
** Kusanagi's are slitted like a cat's. {{Lampshaded}} in one of the {{omake}}s.
** Murakumo's have the whites and the pupils inverted, colorwise, in one form.
* HotSpringsEpisode: The third {{OVA}} episode, in which the team must deal with a bomber and some monkeys.
* HunterOfHisOwnKind: Kusanagi and Murakumo, though in the case of the later, it's dealing with rouge MonsterOfTheWeek types going against the master plan.
* IdolSinger: One episode has a contest for it, that Momiji is tricked into entering. It's actually justified because her [[VoiceActors voice actress]] is also a singer.
* IHaveTheHighGround: Murakumo loves doing this.
* TheImperialRegalia: The Imperial Regalia of Japan provide names and imagery throughout the series -- see the entry for MeaningfulName below, for one example.
* ImprobableAge: Kunikida is in his 40s, Matsudaira is 32, and Kusanagi is 18.
* InformedFlaw: Matsudaira claims to have been a bad wife and a worse mother, but her son and ex-husband seem to hold her in high regard.
* InSeriesNickname: Koume "The Hurricane" Sawaguchi. Momiji is referred to by more than one character as [[HumanSacrifice "Sacrifice Girl"]] throughout the series, most frequently by Sakura, whom herself [[ButNotTooForeign has a bit of difficulty with the Japanese language]] and will accidentally refer to her as "Orifice Girl".
* JustEatGilligan: A fairly major plot point [[InUniverse in the series]]. If Momiji croaks, the Arigami go away, and several individuals and groups in the series are attempting to cause just that. However, aside from the ethical complications of human sacrifice, it's implied this is more of a stop-gap solution and the TAC is attempting to find a more permanent end to the Arigami.
* LamePunReaction: Most of the TAC groans or even vacates the room from Kunikida's puns, though at least one got an ActuallyPrettyFunny response from them.
* LeaningOnTheFourthWall: In the {{OVA}}s
* LimitedWardrobe: One {{omake}} has Matsudaira [[LampshadeHanging wondering]] why Kusanagi always wears the same clothes and if he ever takes them to be cleaned. This is even more amusing when you consider that Kusanagi's trademark red coat tends to get literally torn into small pieces during his transformations, yet in the next episode it is usually seen again, undamaged.
* MarilynManeuver: Momiji in episode 10 in one of several panty shot scenes.
* MarriedToTheJob: Matsudaira. There's an entire episode surrounding how her work is pulling her away from her son.
* MayDecemberRomance: [[spoiler: Ryoko Takeuchi and Daitetsu Kunikida]]
* MeaningfulName: Kusanagi Mamoru. Mamoru mean "to protect," and {{Kusanagi}} is the holy sword of the Japanese emperors, which apparently once belonged to Susano-o. It means the grass cutting sword (long story). Murakumo, the cloud cluster sword, is another name for the same sword and is the name of another character. He's trying to kill Kusanagi.
** Also in the second episode, Momiji (whose name means maple leaf) leaves little maple-leaf shaped pastries for the TAC team in order to endear them to her.
* MediumAwareness: One omake has Kunikida and Takeuchi explore the perils of animation cells.
%%* MonsterOfTheWeek
* MoreDakka: Koume's battle philosophy resolves around this.
* MysteriousProtector: Kusanagi, at least after the first two episodes when he comes to accept that killing Momiji is something he just can't do.
* NoDressCode: Outfits in the office run the gamut from reasonable suit and tie to Koume's pink jumpsuit.
* OfficeRomance: Between [[spoiler: Ryoko and Kunikida]]
* OffscreenBreakup: [[spoiler: Happens between Blue Seed 1 and Blue Seed 2 for Koume and Yaegashi. Momiji directly asks Koume at one point why they broke up, to which Koume replies that she and Yaegashi had been talking about getting married and having kids, with the inference that Yaegashi may have proposed. She got got cold feet and broke it off, even going so far as to ''transfer divisions and relocate'' in order to get away. After Momiji cries that if Koume loves him then it's the right thing to do, Koume reconsiders and by the end of the episode she accepts his proposal, telling him to get her a ring [[RelationshipUpgrade "worth at least three month's salary."]]]]
* OffscreenVillainDarkMatter: Normally not a concern of the Aragami, but episode 7 revolved around their attempts to gain more of the special ceramic needed to nullify Momiji's powers.
* {{Omake}}: Thirteen shorts poking fun at the show, and some animation conventions.
* {{Onmyodo}}: Sakura's magic.
* OpaqueNerdGlasses: Sakura, when she's in {{miko}} mode.
* OppositesAttract: [[spoiler: Koume and Yaegashi]].
* OrdinaryHighSchoolStudent: Momiji.
* {{Orochi}}: One of the aragami.
* PantyShot: Apparently Momiji cannot walk five feet without exposing her cute cartoon character underwear -- at least until the MoodWhiplash.
* PatrioticFervor: "What happiness it is to be born Japanese!"
* PolarOppositeTwins: Kaede and Momiji.
* PowerPerversionPotential: Yaegashi's computer program to predict the weakness of enemies can also be used to figure out what kind of panties Momiji would be wearing that day. She was unamused.
* PunchCatch: Murakumo pulls this on Kusanagi in episode 12.
* RaisedByDudes: Inverted by Yaegashi, whose father was high up in the Defense Ministry and was never home, thus leaving him to be raised solely by his mother and two older sisters.
* RealTrailerFakeMovie: One of the Omake shorts makes the series look like a {{Toku}} {{Kaiju}} film. The English dub even has [[SoBadItsGood intentional crappy voice acting and lip-synching]].
* RecklessGunUsage: Yaegashi's first time with a rocket launcher. He can't find the safety and ends up doing the old "peer down the barrel" bit. It's something when Momiji is able to use it better than he can.
* ReplacementGoldfish: Momiji's twin sister was no longer available to be used to quell the problem, so the job fell to her.
* ReverseMole: [[spoiler:Kaede had been playing the Aragami from the start: She always intended to hijack the end-of-the-world ritual to renew the Earth's resources instead.]]
* TheRival:
** Kusanagi and Murakumo, both acting as protector to their chosen person. It takes until the final episodes before Kusanagi is strong enough to finally give Murakumo a run for this money. Before then, he could barely land a hit.
** Yaegashi thinks he's this to Kusanagi for Momiji.
* RunningGag: OnceAnEpisode Momiji's underwear [[PantyShot gets exposed]], along with the cute picture of a cartoon animal on them, much to her embarrassment.
** Also, less frequently, Kusanagi teasing Momiji about her chest size.
* SacredFirstKiss: Kusanagi once had to revive Momiji with CPR. She spends the episode fretting if it counted as this or not.
* ScienceHero: Matsudaira and Yaegashi both fall into this trope (as the science and technology experts respectively). They prove their worth by assessing, researching, and executing effective ways to kill the Aragami.
* SeparatedAtBirth: Momiji and Kaede.
* ShipperOnDeck: Koume ships Kusanagi/Momiji and Matsudaira ships Ryoko/Kunikida.
* ShouldersOfDoom: Apparently, going all out with mitama powers gives you really big shoulder armor.
%%* ShrinesAndTemples
* SmallGirlBigGun: Koume. Momiji also isn't afraid to fire a rocket launcher as needed.
* SoulJar: The mitama, which are essentially the physical form of the Aragami and house their spirits.
* SpoilerOpening: [[spoiler:If Kaede is supposed to be dead, why does she keep showing up in the opening credits?]]
* SuperDeformed: In the {{omake}}.
* SurprisinglyGoodEnglish: The US Navy officers were voiced by American actors and are a big contrast to FakeAmerican Sakura.
* TeamMom: Azusa Matsudaira, interestingly also explored in that she openly admits that she's a horrible mother to her young son Jun.
* TheCharmer: Sugishita likes to think he's this when in fact he's actually more of the series ButtMonkey.
* TheNineties: The hair, the outfits, the cell phones, the cars...
* ThemeNaming: Besides the {{Meaningful Name}}s, every important character is named after trees. The [[ThemeTwinNaming twins Kaede and Momiji]] are named by two words for the same tree, the maple.
* ThemeTuneCameo: Momiji hums the ending in an {{omake}}.
* TheyCallMeMisterTibbs: Yaegashi whines throughout the second episode that he's the only person in the TAC to not be addressed with an honorific, specifically "san" ("Mr."). He tries correcting his teammates on this several times, but they all brush him off. This becomes a plot point again in [[ADayInTheLimelight another early episode]] when he complains that no one in the TAC respects him or takes him seriously.
* TitleDrop: The term "blue seed" is used to refer to the Aragami's physical form for a few episodes before the term "mitama" becomes commonplace.
* ToBeLawfulOrGood: Obey the government's direct orders to sacrifice Momiji, or go rogue to defeat the Aragami using a yet-to-be-determined alternative?
* TokyoIsTheCenterOfTheUniverse: It's really amazing how many bad things happen there, and no wonder why at the end of the series, America has sent a fleet to just put it out of its misery.
* TookALevelInBadass: Yoshiki Yaegashi starts out as a wimpy computer nerd, but mans up by the end of the series and gets the girl [[spoiler: - Koume Sawaguch that is.]]
* TwoActStructure: The first 13 episodes are standard MonsterOfTheWeek fare that serves to set up the premise and flesh out the characters. Once Kaede pops back up, the remaining 13 episodes has things get darker and focuses on setting up for the finale.
* UniversalDriversLicense: Valencia can pilot a helicopter without any supervision. She's 16.
* UnusualEars: Murakumo's are pointed, as are Valencia's.
* UtopiaJustifiesTheMeans: Kaede and Susano-oh's goal is to turn Japan into a green, unpolluted paradise... by turning all the humans into plants. [[spoiler: Not really. Kaede had her own plans.]]
%%* VirginPower
* WhamEpisode: [[spoiler:Episode 13. Momiji comes to accept that she's in love with Kusanagi. The Aragami are revealed to have a plan and successfully resurrect their god Susano-oh. Also, Kaede is revealed to be alive and having joined the Aragami.]]
* WhipItGood: Valencia uses one.
* YouGottaHaveBlueHair: Ryoko has purple hair, which could be written off as stylized black. Kusanagi and Susano-oh have green hair, which is {{justified|Trope}} by their connection to aragami. But then you get Valencia, whose hair is bright pink and Koume, whose hair is [[FieryRedhead orange]].