Den-noh Coil (Cyber Coil in English), also known as Coil -- A Circle of Children, is an Anime First sci-fi series animated by studio Madhouse and made its original run on Japanese public network NHK in 2007.
Den-noh Coil is set Twenty Minutes Into the Future (in 2026, to be exact) in the fictional Japanese town of Daikoku, which is the testing ground for an Augmented Reality project that involves crafting a cyberspace that overlaps the town entirely. By using specific glasses, people are able to interact with this overlapping cyberspace, allowing them to carry on their normal lives in addition to being permanently connected to the internet through their glasses, essentially concentrating all modern portable media devices (phones, MP3 players, laptop) into one set of non-intrusive glasses. With the appearances of 'glitches' in this augmented reality, a thriving hacker culture soon emerges amongst the children of the city.
The anime tells the story of Yuko Okonogi (nicknamed "Yasako"), a girl who moves into Daikoku together with her mother, little sister Kyoko and her virtual pet Densuke (an augmented reality dog that only people with glasses can see) when her father gets a job transfer there. Upon arriving in the town, she finds herself integrated into the glasses community of the local children, and discovers that her shrewd grandmother has become a focal point for a major club of these children, called the Coil Cyberinvestigation Agency. This leads to later encounters with the enigmatic Yuko Amasawa (nicknamed "Isako"), a girl with abnormally powerful hacking skills who seems to be hunting for computer viruses in the system known as "illegals" for her own unknown ends, and discoveries tying the various characters' pasts with the truths behind the city's cyber-network...
Den-noh Coil could be described as "Ghost in the Shell: Stand Alone Complex meets Hayao Miyazaki"; an extremely charming, high-quality story of children, for children, in a sci-fi setting designed to display the effects of this new technology that still manages to keep some "magical" aspects. Despite winning several prizes, reaching cult hit status and being critically considered to be one of the best animes of 2007, the series was only licensed in 2011 by Tokuma Shoten for use in an iPhone app. It finally received an English translated release (sub and dub) in 2016, from Maiden Japan, and the translation didn't appear on Netflix until 2022.
- Adults Are Useless:
- Justified somewhat, as the use of glasses is mostly a children's fad and most adults do not use them... Though the few that do are usually as competent as the rest of the cast.
- Justified somewhat as far as the events of the story are concerned. Much of the plot is due to early adult experiments with cyberglasses.
- Subverted towards the end - Mega-Baa and Yasako's dad are crucial for solving the crisis, even though Yasako still has to go to the front line.
- The Atoner: Haraken is this at the ripe old age of 11. In the final episode, he learns it wasn't his fault.
- All Myths Are True: There are tons and tons of urban legends and myths kids make up about cyberspace. Many of the ones mentioned throughout the series are proven to be true to some degree.
- Alternate Character Reading: The basis of the Yukos' nicknames.
- Annoying Younger Sibling: Kyoko, to the Nth degree.
- Arc Number: 4423
- As You Know: Takeru gets one from his brother, Nekome, and we get some late exposition Nekome's motives in bringing down the company.
- Augmented Reality Game: The story is set in both reality and Virtual Reality, and includes points where the two overlap and effectively become Augmented Reality.
- Bag of Holding: Fumie has one; justified since the programs she carries in it have no actual physical space requirements.
- Beam Spam: Searchy's ultimate attack mode. That it's virtual doesn't make it any less frightening, considering what happens to people who lose their virtual bodies on The Other Side.
- Beard of Evil: Kinda-example: An illegal beard shows up halfway through the show. It's infectious. And sentient. The different characters' beards eventually start digi-nuclear warfare with each other using Inter-Facial Ballistic Missiles. We couldn't make this up if we tried.
- Even performs a Heel Face Turn after the ensuing holocaust.
- While the episode is a completely anvilicious author tract about war, it's also the first indication the viewers get that an illegal can be sentient, which is important later on.
- Biker Babe: Tamako
- Boisterous Bruiser: Daichi's father seems to be this.
- Blind Idiot Translation: The most popular fansub called Searchy "Satchii", Q-chan "Kyuu-chan", and Midget "Micet".
- Blob Monster: The first illegals to show up are mostly indistinct 'blobs' of black.
- Bratty Half-Pint: Daichi.
- Breather Episode[context?]
- Butt Monkey: Daichi goes through more
hilariousunnecessary suffering than anyone else.
- But Now I Must Go: Isako, in the end
- Chekhov's Gun:
- The Coil Detective Agency badges. Specifically members one, two, and three.
- The keyhole in Densuke's collar is visible from the earliest episodes.
- The very first few seconds of the opening theme.
- Cherry Blossoms: In the final episode.
- Chew Toy: Daichi.
- Combining Mecha: Searchy.
- Cool Big Sis: Technically a 'Cool Aunt'; but Tamako otherwise fits this Trope to a T (no pun intended).
- Cool Old Lady: Megabaa.
- Crack! Oh, My Back!: Mega-Baa, of course.
- Dangerous Forbidden Technique: Imago, which turns out to cause nerve damage and even heart disease! Isako even explicitly warns Yasako not to use it, or else risk death.
- Dark Magical Girl: Isako, only with hacker skills instead of magic.
- Dead Little Sister: It's a big brother, and it's Isako's, but otherwise follows the trope to a tee.
- Death by Newbery Medal: Oh, Daiichi.
- Defictionalization: Fans of the show will be delighted by the announcement of project Google Glass.
- Dueling Hackers
- Dummied Out: This is what happens to any plot of Cyberspace deemed "obsolete". They're deleted periodically, but if you get to them before that happens, you might find Metabugs – items no longer considered valid, which by some accident are very useful in Item Crafting.
- Dying Declaration of Love: Yasako to Haraken in episode 20
- Earn Your Happy Ending: Explaining exactly how would be a major spoiler.
- Empathic Environment: In the sleepover episode, during the scary story telling scene, Daichi's ominous words are followed by thunder and lightning, though this was revealed to be his friend's doing. However, when Haraken tells his story, the lightning appears to be real.
- Enigmatic Minion: Isako would be a prime candidate for this... if she was the actual minion of someone. The show sets her up to look like Nekome's minion, but both his and her actions in the last half-dozen episodes shows that she's anything but.
- Everything's Better with Dinosaurs: Digital plesiosaurs, for the win.
- Everything Is Online: Well, it's set Twenty Minutes Into the Future but still. Traffic lights and lift controls are a bit egregious.
- Filler: Most of the episodes without Isako can be considered to be either filler or to be giving background flavor - although some of that background becomes important in later episodes.
- Five-Man Band
- The Hero: Yasako
- The Lancer: Fumie
- The Smart Guy: Haraken
- The Big Guy: Daichi
- The Chick: Denpa
- Sixth Ranger: Isako
- Tagalong Kid: Kyoko
- Team Pet: Densuke
- Fluffy Tamer: Tamako, who controls the Searchys and Q-chans, gives them affectionate pet names, and even treats them as pets as much as servants.
- Funbag Airbag: Rushing due to being Late for School, Daichi runs right into Tamako's boobs in episode 21.
- Genki Girl: Fumie, to an extent.
- Girls with Moustaches: Several characters, including girls, sprout sentient virtual facial hair for an episode.
- God Guise: ...Did we mention that the above-mentioned beards start worshiping the people they're on as gods?
- Goggles Do Something Unusual: VR Goggles!
- Green-Eyed Monster: Isako's insecurity over her brother leaving her ultimately manifests itself into the form of Miss Michiko
- Headbutt of Love: Between Yasako and Isako, of all people, in the last episode. And it's obviously sisterly love, not Les Yay.
- Heel Face Turn: Takeru
- Heroic RROD: How Yasako's grandfather died.
- Also self-induced by Isako to make her glyph reactor unstable and interfere with Nekome's passage.
- Heroic Dog: Densuke. Just Densuke. Considering he fights off a group of Nulls while being badly injured himself to protect Yasako, he's a pretty heroic dog.
- Hey, It's That Voice!:
- Isako is Claymore #47.
- Haraken is the Fullmetal Alchemist and The Digimon Kaiser.
- Tamako is Reki, another Cool Big Sis.
- Yasako is Rukia Kuchiki and Shirley Fenette.
- Hold the Line: Tamako's task in episode 20, where she has to hold off the scheduled area formatting long enough for Yasako to return from the obsolete space with Haraken.
- Holographic Terminal
- Hypercompetent Sidekick: Denpa... Sort of.
- Hyperlink Story: Oh, yes. With Yasako wandering into Coil Space kicking things off, we have Isako's search for her brother's cure, Tamako and "the incident four years ago", Sousuke and Nekome and their revenge scheme, and Haraken and his investigation on Kanna's death. This links to Megabaa and Grandpa Okonogi's backstory and the founding of Coil Space, which loops back to Yasako wandering into Coil Space.
- Implacable Man: Searchy, at least from the protagonists' point of view.
- Plus, he can be stopped at least temporarily with the use of some hacking.
- Important Haircut: Variant: While Isako's hair isn't cut, her hairstyle gets changed at the end of the series to symbolize a break from her dependence on her brother.
- Instant Runes: The metatags seem to function a lot like this, even though the setting is non-magical.
- Subverted with Isako who actually draws patterns that perform all kinds of functions, like dealing with Searchy.
- Manifested later on with Imago.
- Jerk with a Heart of Gold: Daichi in the end.
- Jerkass: Daichi in the beginning.
- Killer Rabbit: Boku Searchy!
- Kimodameshi: With computer-generated scares, no less.
- The Load: Kyoko, most of the time.
- Picture Mei-chan with poop jokes. And lasers.
- Locked in a Room: Yasako and Isako are locked inside a storage locker in one episode. Nothing notable happens apart from showing that Isako isn't particularly villainous.
- Lotus Eater Machine: Isako in the final two episodes
- Magic Skirt: except for Kyoko
- Manipulative Bastard: Nekome, in spades.
- Meaningful Name: Both Yukos, 優子, "kind girl" for Okonogi, and 勇子, "brave girl" for Amasawa. Lampshaded when the first one, "Yasako", explains her nickname and gives the other one hers.
- Meganekko: Most of the female cast, for obvious reasons.
- Yasako still can be labeled as one though, since her glasses have an ordinary shape, whereas most other girls wear goggles.
- The Messiah: Yasako.
- Minus World: Obsolete Space.
- The Missingno: "Illegals" are sentient viruses that subsist on metabugs. They might have been regular cyberpets - or other code, or something else - once, but the material they were made from is no longer valid.
- Mood Whiplash: Episode 12 is a Crowning Moment of Funny, while the next is an immense Tear Jerker.
- Mohs Scale of Sci Fi Hardness: While the theory behind the glasses themselves is very plausible, the fantasy elements present in the net are certainly not.
- Ms. Exposition: Tamako plays this role a lot.
- Ms. Fanservice: Also Tamako... Not that she has a lot of competition here.
- New Transfer Student: Yasako and Isako.
- Never Mess With Mega-baa
- No Infantile Amnesia: Averted, as it's at least part of the reason Yasako and Isako don't completely remember past events (from when they were around seven) until the story's climax.
- Not So Stoic: Isako. Oh, Isako.
- Old Master: Megabaa again.
- Ominous Fog: Of the virtual kind and usually an indication that something doesn't compute.
- Once Per Episode: Every episode will start with Yasako delivering an update on the latest rumors on the net, which are almost always relevant for the ensuing episode.
- One Steve Limit: Averted by the two Yukos... but, since most people use their nicknames, it doesn't matter until the story's climax.
- Opt Out: Fumie, after an encounter with Illegals that almost costs them Kyoko, tells Yasako she doesn't want anything more to do with researching them.
- Pet the Dog: Almost all of the more morally ambiguous characters have one, to show they're not really bad people. It is a kid's show, after all.
- Plucky Girl: Most of the female cast.
- Point of Interest: Due to being set in virtual reality and reality, there's a few points. Searchys can't enter any shrines, which gives mischievous or worst, bad egg, kids insanely good places to hide. In addition, the VR space, which is home to 4423 got a fixed entry point that leads to the real world's settings.
- Post Cyber Punk: To the degree that there's not much punk left.
- Posthumous Character: Kanna, Yasako's grandfather, and Isako's brother
- Power Degeneration: Isako using/controlling the Imago along with a glyph engine is one helluva powerful thing and very few people can manage it, but it does severe damage to your nerves and body.
- Rapid-Fire Typing: Pretty much everyone who types, though Isako has a powerful variant: Rapid Eye Clicking
- Recap Episode: Episode 14 is mainly this, with some plot in the last minutes.
- Revenge Before Reason: Nekome, in his growing desperation to destroy MegaMass
- Ridiculous Future Inflation: Parodied in Mega-baa's store. 10 seconds of Megane-beam costs "three million yen" (roughly 30,000 US dollars.) Fumie pays with pocket change. Mega-baa's idiosyncrasies are many.
- To be clear, Mega-baa is just being weird by multiplying all the numbers she says by ten thousand. She asks for a total of 6.2 million yen, but the register actually says the total is 620 yen (about five dollars), and Fumie pays with recognizable Japanese coins that add up to that amount.
- Ridiculously Cute Critter: Isako's henchmen, or Mojo, are a sort of terribly adorable virtual fluff balls. The Midgets are unspeakably cute as well.
- Romantic Two-Girl Friendship: Unusually for a Shoujo Action Girl show, Isako and Yasako never quite get there, although they come awfully close at times
- Sacred First Kiss: Daichi makes a huge fuss over the fact that his First Kiss is stolen without his consent... by Yasako's little sister.
- Scenery Porn
- She's Got Legs: Isako, for a sixth-grade student. This is only prominent when she sits down, legs crossed.
- Shout-Out: Most everyone (even Searchy at the end!) uses Mikuru beams, even if they call them megane-beams.
- Shrines and Temples: Daikoku city has quite a lot of these – handy, since Searchy is forbidden from entering them.
- Shrinking Violet: Haraken and Denpa are male examples.
- Spam Attack: Daichi tries to attack Isako by spamming her with email. Isako not only deletes the mail faster than Daichi can send it, but she also spams Daichi back, ultimately crashing his glasses and forcing an expensive restore.
- Spanner in the Works: Yasako, her encounter with 4423 inadvertently messed up the therapeutic intent of the Coil Domain and partially created Miss Michiko.
- Spirit Advisor: Densuke -- being a virtual pet, only people with glasses can see him.
- Stringy-Haired Ghost Girl: One explanation of what "Miss Michiko" is entails an onryo-ish death and onryo-ish behavior, but as the story is told, a pure black figure is used to represent her ghost instead of typical onryo garb and appearance, probably to liken her to an Illegal, and Yasako flat-out says she's an Illegal in the final episode.
- Taking You with Me: In the last episode, Tama Kamikaze-dives with a Nekome-controlled Searchy 2.0 in negative space.
- Team Pet: Densuke.
- Techno Babble: "Quantum" has the same meaning in this story that it does on the Discworld.
- Tomato in the Mirror: The other urban legend explaining exactly what the mysterious "Miss Michiko" is ends with this.
- Title Drop: The phenomenon known as Den-noh Coil isn't referred to by name until episode 14.
- True Companions: At the end of the series, Isako tells Yasako what basically amounts to "I still don't know the meaning of 'friends,' but we'll always be Nakama."
- Two Scenes, One Dialogue: Happens quite a few times in the later episodes,often involving Tamako.
- Undisclosed Funds: Virtually every major expense by the children is simply referred to as "x years' worth of otoshidama". Reformatting their glasses costs "two years of allowance"! Even a single year of otoshidama is a significant amount of money to those without jobs!
- Unusual User Interface: Some people like Isako can use their glasses without performing any outward physical actions.
- The glasses period. The things you can do with them is crazy.
- Virtual Ghost: The Nulls.
- Wham! Episode: Episode 21. Holy crap episode 21.
- What Do You Mean It Wasn't Made on Drugs?: How else would you explain the beard episode?
- When It All Began: Kanna's accident one year ago, and Isako's accident 5 years ago.
- Wise Beyond Their Years: Isako. Big time.
- Your Mind Makes It Real: Lots.
- Miss Michiko, which took two minds to make real.