Being stalked by a secret organization doing their own Time Travel experiments and dead-set on capturing or eliminating you? Not so awesome.
The Spiritual Successor to Chaos;Head, Steins;Gate is set roughly one year after the events of the previous game, in the Akihabara area. Like most of his friends, Rintaro Okabe loves experimenting, tinkering with different gadgets and inventions. However, he's taken this love so far as to declare himself a Mad Scientist, and prefers to go by the alias Kyouma Hououin. One fateful morning (July 28, 2010, to be precise), he and his ditzy childhood friend Mayuri Shiina discover the body of Kurisu Makise, a celebrated researcher. As they flee the scene, and he texts his buddy Hashida Itaru, everyone around them briefly vanishes... yet nobody else seems to have noticed the incident.
Shortly thereafter, Rintaro and Hashida run into Kurisu, very much alive, and Hashida mentions receiving a text babbling about the discovery one week ago. Investigating further, they realize that by constantly upgrading and customizing their microwave, they've stumbled across the secret of Time Travel... or, at least, sending text messages back in time, which is a starting point, right?
Unfortunately, they're not the only ones interested in time travel. The shadowy organization SERN has been running their own experiments, and thanks to Rintaro's frantic text to Hashida, they've clued in to what Rintaro and his friends have discovered, and are closing in...
Instead of the "delusion trigger" system introduced in Chaos;Head, Steins;Gate uses the similar "phone trigger": whenever somebody calls Rintaro, he can choose whether or not to answer. Text messages include blue hyperlinks that can be selected to reply to the text. The player's choices determine what sort of path the plot takes.
Two manga adaptations have begun: one by Sarachi Yomi is serialized in Monthly Comic Alive, while the other, by Kenji Mizuta, is printed in Monthly Comic Blade.
A 24-episode anime adaptation aired starting in the Spring 2011 Anime season. Following the end of the anime's broadcast, a twenty-fifth episode was released straight to video and a theatrical film was announced.
A full fan translation of the game exists: also the same thing which happened to Chaos;Head's translation project is true to this one, the fan translators pulled the patch from their site as JAST expressed interest in localizing the game. The fans are expecting the worst, as the original agreement with Chaos;Head lead to nowhere, resulting in fans losing the patch and hope for a licensed release.
An official English translation was released on Steam in August of 2016.
- Accidental Innuendo: Itaru generally requests an immediate repeat whenever they come up.
- Accidental Pervert:
- Rintaro's attempt to confirm Ruka's gender after making him a her going wrong.
- After receiving another threatening message, Rintaro rushes to his apartment, and finds Mayuri and Kurisu in the shower.
- Alternate Character Reading: Invoked with Rintaro's name for the time machine e-mails, "Nostalgia Drive". It's written "time-travelling journey for nostalgia" (時を越えた郷愁への旅).
- Anime of the Game
- Another Dimension: Happens almost every time Rintaro sends a D-Mail.
- Arc Words: Subverted. Rintaro loves throwing around the words "Steins Gate" and "El Psy Congroo", but he himself admits that those words don't have any meaning whatsoever.
- Back from the Dead: Happens to Mayuri whenever Rintaro goes back in time. Somewhat subverted in that unless something drastic in time is changed, death will almost certainly occur again.
- Bad Future: Alpha timeline where SERN successfully creates the time machine, using it to create a Dystopia under their rule and Beta timeline where Kurisu dies and World War III happens.
- Gamma timeline takes it a step further, since in this timeline, Okabe becomes a part of the rounders along with Moeka.
- Based on a Great Big Lie: Based on John Titor's time traveling story, it could be either true or false and he's a girl.
- Because Destiny Says So: Unless Rintaro manages to change the attractor field, a person's death can never be changed. This also applies to his own death, as in both the Alpha and Beta timelines, he will not live past 2025.
- Belligerent Sexual Tension: Rintaro and Kurisu.
- Berserk Button: When Faris mentions in the Alpha drama CD that her maid outfits might not fit Kurisu, Kurisu gets awfully touchy.
Faris: Ah...! But... [my] clothes might not fit on fit on you, nyan.
- Big Damn Heroes: Just when SERN is about to capture the group, Suzuha saves them and asks Rintaro to time leap.
- Big Fancy House: Played with considering Faris's living quarters. It's not necessarily big, but it's a lavish living space on the top floor of an expensive building that reveals just how rich Faris is.
- Bishie Sparkle: Ruka (but he's a guy).
- Bishonen: Ruka, at least in most timelines.
- Bittersweet Ending: In the true ending, Rintaro prevents both bad futures and Kurisu's death, but with the exception of Rintaro, none of the Lab Members retain any memories of their experiences, and Suzuha completely disappears as a result of the Time Paradox (as there's a chance she might never be born in the future of the new timeline). However, it is hinted that the members might not have completely forgotten their memories, as shown when Rintaro meets Kurisu again in Akihabara, and she still has memories of the nicknames Rintaro gave to her.
- However, despite that, many of the characters that would have suffered Downer Ending fates have their lives turned around. Since he doesn't have to spy on the lab, Mr. Braun is still alive and hires Moeka to be his store assistant, Moeka herself shows signs of opening up to others, and Mayuri and Kurisu both survive. Plus, if Suzuha is ever born (and it is strongly hinted that she will), she won't be born into a dystopia or post apocalyptic world.
- Bland-Name Product: SERN and IBN play an important part in the plot. However, there's also Goodle, MewTube, |CLADANDAN, KBA84 and Comima.
- Averted with Dr. Pepper.
- DK. Pepper. Also, UNIQLO, but the bottom half of the logo's blocked out.
- Averted with Dr. Pepper.
- A Bloody Mess: Averted. Rintaro originally intends to use the red liquid inside a glow-in-the-dark lightsaber toy as part of his plan to fool his past self into thinking Kurisu's dead, but upon discovering that it's dried up and useless, he provokes Dr. Nakabachi into stabbing himself so that he can use his own, genuine blood instead.
- Boobs of Steel: Suzuha, shown later in the series to be capable of taking out a handful of gunman with punches and kicks: despite her having a petite frame, her breasts are larger than any other character besides Moeka, who also kicks serious butt, albeit not physically.
- Braids of Action: Also Suzuha. Goodness, it's almost as if the writers were hinting that she was a fighter!
- Broken Bird: Kurisu, Suzuha and Moeka.
- Broken Pedestal: Dr. Nakabachi is Kurisu Makise's father, and she does everything in her power to impress him and rebuild their damaged father-daughter relationship; she even gives offers him a co-writer credit on a paper on how to construct a time machine, and he repays the favor by beating her and stealing the paper for himself.
- Butterfly of Doom: Multiple examples. At times, the things that randomly stay the same are even more bewildering than the things that randomly change; for example, changing Ruka's gender alters nothing about her personality or appearance, and it also doesn't change anything about the group's dynamic. However, it also starts a chain of events that causes her to accidentally break the IBN 5100, rather than hand it over if he were still a boy.
- But Thou Must!: Most calls or texts can be ignored at will, but there are certain points where Rintaro has to take some sort of action.
- Butt Monkey: Rintaro. Almost none of the cast takes him seriously during the first half of the story because of his behavior.
- Call Back: Episode 25, that dude who was selling brooches in Japan is in fact also a taxi driver in LA. And another one which is much relevant to the plot, see Love Confession below.
- Calling Your Attacks: Rintaro and Faris are anime, manga and moe junkies. As a result, they role-play in some of the more comedic scenes of the anime, which usually involves them revealing that they've learned a secret technique or two while punching the air or doing some dramatic motion.
- The Cameo: Takumi is briefly mentioned by his pseudonym Knighthart looking for IBN 5100. He has no involvement in the story, however.
- A huge TV airing FES's performance in Alpha timeline. Giving the right reply to Faris's mail earns the player Ayase's portrait and FES's music, sang by Kanako Itō, including Chaos;Head OP: "Find the Blue".
- Even Seira-tan appears. Some of the characters from Steins;Gate have also found themselves in other media. Kurisu appears as a character spell in Hyperdimension Neptunia mk2; Mayuri also makes an appearance as a summon. Kurisu's also a character in Phantom Breaker, as well as in Nendoroid Generation.
- Posters of other 5pb. and Nitro+ works occasionally appear in various locations. Additionally one of the computer shops bears the name 'Nitro+' in an alpha worldline, there is also a 'Nitro+' magazine.
- A huge TV airing FES's performance in Alpha timeline. Giving the right reply to Faris's mail earns the player Ayase's portrait and FES's music, sang by Kanako Itō, including Chaos;Head OP: "Find the Blue".
- Catch Phrase: Mayuri's "Tuturu~" whenever she greets someone as a phone wallpaper sent by Mayuri.
- Cat Smile: Faris (of course), Mayuri and Suzuka.
- Cerebus Syndrome: The series starts off as reasonably light-hearted (not that it didn't have its occasional dark moments), but when episode 12 comes around, and Mayuri dies, the emotional intensity is cranked Up to Eleven.
- Character-Magnetic Team: Most of the cast are lab members. Though it's somewhat subverted because several years pass between the formation of the lab and the addition of new members apart from the original three (Daru, Mayuri, Okabe).
- Chekhov's Gun: Remember the Metal Oopa that Mayuri lost in episode 1? 22 episodes later, it was revealed that the Metal Oopa set off the metal detector, prevented Dr. Nakabachi from boarding the plane that was fated to crash. As a result, the documents and research data of Kurisu was not destroyed in the crash, setting off the events for the dystopia.
- Chekhov's Gunman: Mister Braun, literally, as he shoots Moeka and himself upon the gang discovering that he is FB.
- Chick Magnet: Rintaro, depending if you view Mayuri's, Ruka's and Faris' feelings towards him as romantic.
- Conspiracy Thriller
- Cosplay Otaku Girl: Mayuri, Faris.
- Crotch Grab Sex Check: Ruka is a girl?!
- Cry Cute: Kurisu in episode 5 of the anime.
- Cut His Heart Out with a Spoon:
Kurisu: One more word and I'll make your neocortex into a flowerpot!
- Cyberpunk: It deals with cyberpunk themes.
- Death Is Cheap: Whenever Mayuri dies, Rintaro time leaps back to several hours or days ago before her death.
- Lampshaded and deconstructed when Rintarou wants to keep time-leaping to try and Take a Third Option to avoid having to let Kurisu be killed: when she says that seeing Mayuri die so many times will destroy him, he notes that he's already gone numb to the experience. Possibly subverted though, since Kurisu at least doesn't believe he could still have a heart and not feel anything at all at the sight; thus, she calls him out on it.
- Deconstruction: To sum it up, time traveling causes Butterfly of Doom.
- It also shows that undoing the alterations caused by time travel may reverse the bad things they caused, but it also negates all the good things, forcing you to let go of the gifts you got from time travel. And even if you go through all the trouble of unaltering the future so SERN doesn't turn the world into a dystopia, that does not mean that other disasters can't happen.
- Design Student's Orgasm: The anime's opening credits sequence.
- Despair Event Horizon: Suzuha upon failing her mission to retrieve IBN 5100 after losing her memory by using her fixed time-machine.
- Determinator: Witnessing Mayuri's death multiple times is not enough to shatter Rintaro's hope to save her.
- Deus Angst Machina: Because Destiny Says So, Mayuri will always die, no matter how unrealistic the circumstances are.
- Disappeared Dad: Faris's father, who died in a plane crash. This makes her use D-Mail to save her father and causes Akihabara to become well-known for electrical appliances instead of otaku culture. In addition, her father saved her from a kidnapping incident by selling his IBN 5100 to SERN in the past.
- The Ditz: Mayuri, who can suddenly stop at a place doing Stardust Handshake, much to the dismay of Rintaro.
- Does This Remind You of Anything?: In episode 19, taken out of context, the brawl Okabe has with Moeka looks very much like a rape in progress.
- The Dog Was the Mastermind: The identity of FB turns out to be none other than Rintaro's beleaguered landlord Mr. Braun.
- Driven to Suicide: Suzuha, after she travels to 1975 using the time machine fixed by Itaru, having lost her memories, then recover it again 25 years later.
- Several characters go through this actually. Moeka hangs herself in one timeline, and Mr. Braun shoots himself in another. Even Okabe tries to kill himself at one point while trying to save Mayuri.
- Dropped a Bridge on Him: Mayuri. Each time she dies, Rintaro time leaps to make sure it never happens.
- Dropped a Bridget On Him: Kurisu, when Ruka's gender is revealed to her, and Rintaro, when Ruka's gender is female due to D-mail.
- Dude Looks Like a Lady: Ruka, very much so.
- Earn Your Happy Ending: And How!
- The Empire: Alpha timeline SERN in the future.
- Everything Trying to Kill You: You are fated to die when the world says so, no time traveling can change that. If the world doesn't want you dead on that moment, you will never die, no matter what.
- Fake-Out Make-Out: Rintaro does this to Moeka when a neighbor comes to see what the source is of all the racket caused by their struggle, and gets bitten for his efforts. Luckily for him, the neighbor failed the spot check for the resulting spectacle ends up looking less like a make-out and more like a rape in progress.
- Fake Band: FES.
- Faking the Dead
- First-Name Basis:
- Rintaro to Kurisu. This specific instance occurs several times, actually because Rintaro continuously reverses the event due to his self-imposed Groundhog Day Loop.
- Faris asks Rintaro to call her by her real name after he saves her from some kidnappers.
- Five-Man Band:
- Foreshadowing: Since this is a series about time travel, there are too many instances of this to list.
- Four Is Death:
- Stage 4 of SERN's Z-Program involves human experiments.
Experiment Result: Human is dead, mismatch.
- Mayuri's last name is Shiina. You can figure out the rest.
- Full-Name Basis: Suzuha, with a few exception, calls people by their full name.
- Funny Schizophrenia: If you are familiar with schizophrenia, then it becomes immediately obvious that Rintaro shows symptoms of it (such as his constant paranoia). However, his schizophrenia is typically used for the sake of humor, and it can enjoyable to understand how his condition affects his mindset over course of the story.
- It soon becomes apparent he does it on purpose, so it wouldn't really qualify as schizophrenia.
- Gamer Chick: Mayuri and Faris.
- Geek Physiques: Rintaro is skinny. Itaru, on the other hand, is extremely fat.
- Gender Bender: Using D-Mail, Rintaro changes Ruka's gender to female. It causes the possibility where she broke IBN 5100.
- Gender Flip: John Titor is Suzuha Amane.
- Get a Hold of Yourself, Man!: Done by Kurisu in Chapter 6, and Mayuri and his future self's D-movie in Chapter 11.
- Gratuitous English: All over the place.
- Gratuitous German: Every now and then. The series' title, for starters.
- Groundhog Day Loop: Rintaro invokes this trope on himself to Set Right What Once Went Wrong using the time leap machine. In Suzuha's route, he refuses to erase Suzuha's memory with the group, using the time leap machine to trap himself in a continuous loop between August 11 to August 13 before Mayuri dies. His heart almost dies before Suzuha saves him and asks him to time travel with her.
- He Knows Too Much: SERN is trying to silence Rintaro and lab members for inventing the time-machine.
- Heroes Want Redheads: Kurisu is Rintaro's love interest and "most important person" in the route that leads to Chapter 11 and the Epilogue (a.k.a. the canon route). Essentially, she's the canon love interest.
- Heroic BSOD: Rintaro, when he lost all his ways to save Mayuri, and upon discovering that he is the one who stabbed Kurisu.
- Heroic Sacrifice: Kurisu decides to sacrifice herself so Mayuri can survive. It doesn't help.
- Hollywood Hacking: Hashida hacks SERN in 2 days. And this is the organization that invented The Internet.
- Somewhat Justified: when Daru was hacking into the SERN in episode 14, he mentions that SERN ports were already open as SERN had been watching the group since the first D-Mail was sent. It's somewhat justified that he would be able to hack into a system quickly that already has its doors open into Daru's computer in the first place.
- Hope Spot: Rintaro initially believes that additional divergence caused by Suzuha's trip to 1975 would subvert Mayuri's murder. Nope.
- Improbable Age: Believe it or not, Faris owns Akihabara, and is responsible for making Akihabara into moe town.
- In-Series Nickname: Fairly much the entire cast:
- Rintaro: Hououin Kyouma, Okarin.
- Mayuri: Mayushii, Tuturu, [[ChuuChuuru]].
- Itaru: Daru, Super Haker, Super Hacker.
- Kurisu: Christina, Assistant, The Zombie, @channeller, Celeb 7, Chestnut Rice and Kamehameha, Class Rep Character.
- Moeka: Shining Finger.
- Suzuha: Weekend Warrior/Baito Senshi, John Titor.
- Ruka: Rukako.
- Yuugo: Mr. Braun, FB.
- Nae: Small Animal.
- Innocent Innuendo: Lampshaded by Itaru every single time, much to Kurisu's annoyance.
- Insane Equals Violent: Moeka totally loses it once she's accepted by FB, and kills Mayuri just because FB told her to.
- I Resemble That Remark:
Kurisu: I'm not a tsundere!
- It Got Worse: Things keeping get worse and worse for Rintaro, starting from visual novel's sixth chapter (episode 12 in the anime).
- It's All My Fault: Upon realizing that his invention D-Mail machine causes all the troubles his lab members are facing.
- Jerk with a Heart of Gold: Rintaro despite his childish and Jerkass antics openly cares for his lab members.
- Karma Houdini: Kurisu's father who does lose the paper that would have made him famous, but still seems to avoid any legal punishment for stabbing Okabe. Even worse, in the other timeline where he was responsible for his daughter's death and then stole her paper, gaining fame and power.
- The anime did not mention about Nakabachi's fate, but in the visual novel, he was arrested in Russia for his outburst and being a suspect for attempted murder in Radio Kaikan building.
- Kid From the Future: Suzuha, to Daru (her mother is never named). She doesn't know who her father is when she gets there either, only that he was there at that time.
- Kill the Cutie: Mayuri is the first to go once things hit the fan... over and over again, thanks to the peculiarities of time travel.
- The Lady's Favour: The only conceivable purpose for a handkerchief that Rintaro knows about.
- Large Ham: Rintaro, oh SO MUCH! It makes him funny and awesome!
- Not like anyone takes his ham seriously other than Ruka or possibly Faris.
- Laser Blade: One of Rintaro's many inventions is the Cyalume Saber, which is pretty obviously Darth Vader's lightsaber.
- Leaning on the Fourth Wall:
- When Rintaro tells Daru about his exploits in previous world lines, Daru jokes that it sounds fantastic enough to be the plot of a light novel.
- A strange variety of this comes up when Mayuri gets Ruka to crossdress and Kurisu stares at him for a little bit (when she thought Ruka was a girl). Itaru even notes how yuri it is with Okabe quickly pointing out that it's not since Ruka's a guy.
- Lighter and Softer: Steins;Gate Hiyoku Renri no Darling, the sequel that focuses less on time travel conspiracies and more on fun and relationships.
- Locked Out of the Loop: Mayuri regarding her fated deaths. However, she frequently has feelings of deja vu about them.
- Loophole Abuse: The finale.
- Love Confession: A very bittersweet one from Okabe to Kurisu in episode 22.
- And a very very manly one from Okabe to Kurisu in episode 25. Note that this occurs in the Steins;Gate world line. He (and the audience) are left hanging at the credits. However, the last thing Kurisu tells him is "Close your eyes", a direct callback to episode 22 that makes it pretty clear what her answer will be.
- Love Makes You Crazy: Yūgo Tennōji (Mr. Braun) loves Nae very dearly, and as a result, SERN threatens him with Nae's death to get him to manipulate Moeka and other people into killing and stealing just to keep the IBN 5100 from reaching Rintaro's hands.
- Luke, You Are My Father: Suzuha travels to year 2010 to look for her father. After Mayuri reveals that Itaru is Suzuha's father, Suzuha hugs Itaru. However, Itaru has no idea why Suzuha hugged him and is left feeling both glad and confused.
- MacGuffin: Nearly half the series is focused around Okabe and SERN's attempts to get their hands on an IBN 5100.
- Madness Mantra: Letter written by Suzuha to Rintaro, filled with despair on how she failed her mission to get IBN 5100 and her life is meaningless. Mission Report: Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... Failure... I failed... Failure... Failure... Failure... Failure... Failure... Failure...
- Also Moeka. After she loses contact with FB, the only thing she can text on her phone is: FBFBFBFBFBFBFBFBFBFBFBFBFBFBFB...
- Mad Scientist: Rintaro, or, as he prefers to call himself, the Crazy Mad Scientist Kyouma Hououin.
- Magical Particle Accelerator: The plot is based on the idea that the Large Hadron Collider has some kind of massive world-ending powers.
- Maybe Ever After: Implied with Rintaro and Kurisu in the true ending.
- Meido: Faris Nyannyan.
- Mental Time Travel: D-Mail and time leap machine.
- Mind Screw: Time traveling will do that to everyone.
- The Mole: Kiryuu Moeka, who is working with SERN to collect IBN 5100, and to capture Rintaro, Kurisu and Itaru for creating D-Mail.
- My Name Is Not CHRISTINA!
- Nakama: Being a Lab member of Future Gadget Circle is like being Rintaro's nakama.
- Never the Selves Shall Meet: This is obviously not a problem considering that Rintaro uses Mental Time Travel, but it comes into play at the end of the series when Suzuha helps him alter the past with a "conventional" time machine.
- Nice Job Breaking It, Hero: By choosing to use D-Mail to mess up the past, Mayuri will die, and SERN is dead set on capturing you.
- The Nicknamer: Rintaro, who enjoys giving other people nicknames based on their deeds, the only one who avoided this is his childhood friend Mayuri. Mayuri also likes giving herself and Rintaro nicknames, much to dear Okarin's displeasure.
- No-Holds-Barred Beatdown: Rintaro fights Moeka in her apartment in order to get her D-Mail message.
- Oh Crap: Rintaro, every time Mayuri's watch stops, since it means that she's about to die again.
- Ojou: Faris, her real name being Rumiho Akiha.
- Otaku: Itaru, who likes both 2D and 3D girls.
- Our Time Travel Is Different
- Overprotective Dad: Yuugo.
- Parental Neglect: Kurisu's father keeps a distance from her, downright refusing to see her.
- Pettanko: Kurisu.
- And female Ruka, though only noted briefly.
- Phrase Catcher: Okabe tends to call people out on the things that he himself does, cue the "You are the last person I want to hear that from" reaction.
- Police Are Useless: Police officers only serve to interfere with Rintaro's actions. They do absolutely nothing when Rintaro and Faris are being hunted by a group of angry mobs all over Akihabara!
- Poor Communication Kills: It takes Rintaro ages to think of telling anyone else about what's going on once things start to go bad. And he never even tries to tell some people, at all, even when they'd logically have a huge amount to contribute and plenty of incentive to do so.
- Post Cyber Punk: It deals with post-cyberpunk themes.
- Pretty Little Headshots: Mayuri's (initial) and Mr. Braun's deaths. The former only shows the requisite trickle of blood down the face, while in the case of the latter, there's no indication at all that that person has even been shot.
- Product Placement: In the anime, Rintaro only drinks Dr Pepper.
- Psychopathic Manchild: Nae upon receiving her 15 years later memories via time leaping.
- Real Place Background: Makise Kurisu's institution in America, Victor Chondria University, is modeled on real world Columbia University. This is seen in depictions of the campus and the university ID card in the manga adaptation of Epigraph of the Closed Curve.
- Many of the locations in the series are based on actual places in Akihabara. Highlights includes MeyQueen NyanNyan which is based on the Mai-lish maid cafe and The Future Gadget lab itself, which is based on an actual shop, if you go by the address that Okabe mentioned in the beginning of the game. Amusingly, there is an HDTV store in the same location where Braun TV should be.
- Redemption Equals Death: Moeka apologizes for her other world line self killing Mayuri after getting stabbed by Nae.
- Rescue Romance: This is how Ruka and Rintaro met. In the timeline where Ruka is a female, she fell in love with him. And hinted that Ruka fell in love in the timeline where he's a guy.
- This is actually a strange example since in the timeline where Ruka is a girl, this didn't actually happen. She was just getting memories from the other timeline. It is interesting to note that she stated that this was the moment she started loving Okabe, implying that may actually be what the male Ruka felt.
- In one of the drama CDs, Ruka's feelings seem to be confirmed when pretty much blurts out his attraction to Okabe to Suzuha (who is currently the victim of a romantic misunderstanding). However, it takes place in a separate world line, so take it as you will.
- Revenge Before Reason: Nae.
- Rewatch Bonus: Gratuitously so. Only natural for a series about time travel of course. Seemingly innocuous details from earlier on becomes important later on, and the last episode/chapter hinges heavily on what happened in the first episode/prologue.
- Ripple-Effect-Proof Memory: Rintaro's 'Reading Steiner', the ability to retain memory of prior timelines. However, if their memories are prodded properly, other characters can remember other world lines: this occurs separately with Faris and Ruka. Later on, we find out that Mayuri and Kurisu have both been dreaming of previous world lines.
- Ripple Effect Indicator: The Divergence Meter, which shows the current world line's percent divergence and how close Rintaro is to succeeding in returning to the beta world line.
- Rock Beats Laser: The IBN 5100 is central to the series despite being an antique computer because it can translate the source code SERN uses in its computers, allowing its owner to hack SERN's computer networks with ease.
- Running Gag: Daru's "could you repeat that".
- Sadistic Choice: Either undo the senders' D-Mail, which cancels their wish and erase their memories, or choose not to and let Mayuri die and go to the respective sender's route. Taking a third option won't work.
- Samus Is a Girl: Done twice. John Titor is revealed to be Suzuha. FB, whom Moeka and Rintaro assume is female due to her writing voice, is revealed to be Mr. Braun.
- Screw Destiny: Rintaro's main goal is to save Mayuri from her fated death by undoing all the time traveling he did.
- This is actually a bit of a weird variety since it was him screwing with destiny to begin with that all of this happened.
- Serious Business: Rai-Net. In one timeline, a group of Rai-Netters attempt to kidnap Faris and beat Rintaro half to death just because she beat them in a tournament.
- Daru, just about anything such as Super Hacker and Maid secret techniques.
- Set Right What Once Went Wrong: The latter half of the story deals with undoing all the D-Mails his lab members did to save Mayuri.
- Shout-Out: Daru's dialogue is occasionally peppered with references to various anime and video games, and before the group manages to settle on D-Mail as the name of their time machine, some of the names they come up with reference The Girl Who Leapt Through Time and Back to The Future.
- In the visual novel, Kurisu mentions as one of the impossibilities of time travel the sheer amount of energy it would take to move at light speeds would almost certainly be at least 1.21 gigawatts.
- Faris makes a mention in episode 2 of months of harsh training in the Guyana Highlands and the death of her master.
- Kurisu's "One more word and I'll make your neocortex into a flowerpot!" line may come from the MO of the first barcode killer of MPD Psycho.
- Shown Their Work: In one timeline of their first meeting, Kurisu lectures Okabe on the impossibilities of time travel; the lecture is cut quickly to a picture of Okabe straggling out of the lecture hall absolutely mauled by Kurisu's arguments. In the visual novel, this lecture scene is shown to the audience and is literally Turned Up to Eleven, with Kurisu mentioning exactly eleven different theories of time travel, subsequently shooting down two of these hypotheses. That the creators took the time to explain the absurdities of theoretical time travel in a visual novel/anime about time travel shows something pretty special.
- Show Within a Show: Thunder Battle Net, as well as Chaos;Head's Blood Tune.
- Shrinking Violet: Moeka is such an extreme case that she prefers texting over talking.
- Ruka too, who is overly easy to spook.
- The Slow Path: Alpha Suzuha's time machine is backwards only.
- On a more constrained scale, so is the Time Leap machine, but Okabe points out that sending your past memories to the future would be completely pointless anyway.
- Someone Has to Die: Occurs when the attempts to avert Mayuri's fate put them on track for the timeline where Kurisu died, forcing them to choose between saving Mayuri or Kurisu. However, when they choose to save Mayuri, their decision gets turned on its head when that just makes things worse.
- Something Only They Would Say: FB gave each member of the Rounders specific codenames that no other member knows. It also becomes the key to finding out FB's true identity (see episode 20 Wham! Line below).
- Stable Time Loop: Suzuha's bicycle is put on the time machine and sent to the past, given to Braun once Suzuha dies, and given back to Suzuha when she arrives at Braun's workplace.
- Stealth Pun: Presumably the joke behind the term "D-Mail".
- Stepford Smiler: Suzuha.
- The Stinger: Episode 22. Despite returning to the beta world line and letting Kurisu die as she originally did, it turns out that the Bad Future has not been averted, but simply shifted from dystopia to World War III. The episode also uses a different, instrumental ending credit track, presumably to entice the viewer into sticking around, since the series had no next episode previews and no real incentive to stay for the credits until this episode.
- Stupid Sexy Ruka: Rintaro's reactions toward Ruka.
Rintaro: My soul... My soul is being devoured!
Kurisu: I'm not crying! I definitely wasn't terrified by a guy screaming in my face, so I definitely didn't start crying from relief afterwards! That's not what happened!
- This is also an interesting moment because of the whole thing with her father later on.
- Take a Third Option: Subverted in that it only causes more trouble later. Example: trying to save Faris's father while asking him to hold IBN 5100 until Rintaro claims it causes Rintaro to get stuck in a world where no one remembers him other than Faris, who is now his lover and Rai-Net Access Battlers partner. Both D-Mail and the time leap machine are never created, and he's forced to start a new life with her.
- Taking the Bullet: Kurisu blocked a stab from Rintaro meant for Dr. Nakabachi, giving him a huge Heroic BSOD. Later, Rintaro provokes Dr. Nakabachi into stabbing him.
- In one of the timelines, when Okabe attempts suicide by getting hit by a car, Mayuri pushes him aside and gets killed that way.
- The Teaser: Used more often than not in the anime.
- Techno Babble: To wit: the Mental Time Travel machine involves compression of computer data via black hole.
- Teen Genius: Kurisu skirts the border of this: she's such a talented neuroscience researcher that she's had her research published in an academic journal at the tender age of 18.
- Theme Naming: Rintaro tends to name endeavors "Operation (figure from Norse Mythology)". Lampshaded by Kurisu, and later by Rintaro when she makes up her own Norse-flavored Operation.
- Third Person Person: Mayuri, referring to herself as Mayushii☆.
- Thirteen Is Unlucky: The SERN raid on the lab and Mayuri's murder in the initial timeline occur on a Friday the 13th.
- This Is Unforgivable!: Rintaro hates Moeka with passion for cold-heartedly killing Mayuri. Subverted later when Moeka dies.
- Time and Relative Dimensions In Space: Discussed in the visual novel as a reason that the jellymen end up in such random locations. Also for that fact that, of the hundred or so tested, only fourteen were found.
- Time Paradox
- Time Travel: Central to the plot, and hitting upon plenty of related tropes, with a healthy dose of Mind Screw and Deconstruction.
- Time Travel Escape: Okabe's meddling with the past gets so bad, he must time travel to undo the changes he's made.
- Title Drop: "This is the choice of Steins Gate!" shows up from the beginning. However, Okabe admits to himself if no one else that it has no real meaning at all. In the True Ending, it finally has a meaning, but it's an assigned one: Future Okabe eventually discovered that there was a theoretical third primary timeline to match Alpha and Beta, but with a less terrible future for the main cast.
- Tomato Surprise: The reveal that Rintaro kills Kurisu in beta timeline in an accident.
- You can change the cause, but never can you change the effect. I think this is more of the case here.
- Took a Level in Badass: In the future, Okabe Rintaro becomes a founder and leader of La Résistance and is known as a famous terrorist working against SERN.
- Trauma Conga Line: Rintaro crosses this multiple times trying to save Mayuri and Kurisu.
- Tricked-Out Time
- Tsundere: Kurisu, Lampshaded by Itaru of course.
- A rare justified example in that Rintaro acts like a raving loon during their first few encounters, and it's only after he demonstrates that he's not a psychopath that she starts to lighten up.
- Twenty Minutes Into the Future
- Verbal Tic: Faris often ends her sentence with nya.
- Villainous Breakdown: Dear god, when Moeka loses contact with FB, she becomes an emotional wreck. Her situation is only worsened when Okabe steals her phone. In the world line where Okabe doesn't arrive at her apartment, Moeka eventually commits suicide in despair.
- Visual Novel: Described by the development team as "a Hypothetical Science ADV".
- "Well Done, Son" Guy: Kurisu desperately wants her father's acknowledgement, which he will never give, and downright hates her. In beta timeline, he steals her thesis about time traveling, planning to take all the credit himself.
- Wham! Episode: Anime episode 12, when the lab members are surrounded by SERN.
- Wham! Line:
- Episode 12:
Moeka: "Shiina Mayuri is not needed." *fires gun at Mayuri*
- Episode 20:
Yuugo: (to Moeka) "You sold us out, M4."
- Episode 22:
Suzuha: "You must stop World War III."-*EPISODE ENDS*
- What Happened to the Mouse?: Amane claimed that Kurisu would work for SERN in the future, but it's never fully addressed or explained why, even by the show's end.
- While not concrete proof that this was the case, Suzuha mentions in the same chapter that SERN wouldn't hesistate to hold family members hostage in order to force researchers like Kurisu to go along with them. Kurisu's frightened reaction over her father at the mention of this makes it seem like a very likely possibility that her involvement with SERN was under duress.
- What the Hell, Hero?: Rintaro, sometimes. The most significant one is when Rintaro chooses let to Mayuri remain dead so Ruka can remain being a girl.
- Wrong Genre Savvy: Rintaro is clearly trying hard to be a Magnificent Bastard like Lelouch, but his initially ordinary life frustrates these ambitions, twisting his lines into comedy, with his friend Itaru claiming he is simply "deluded", even admitting that he (Rintaro) is the only one who really cares about "destroying the ruling structure of the world." By the end, however, this is reversed, and those same lines sound downright awesome, and very convincing, notably at the end of episode 23.
- Yandere: Nae, 15 years in the future, time leaps to the present to kill Moeka for being unable to prevent her father's suicide, then warns Rintaro that she will torture him to death 15 years later before running away. All because she is not satisfied with killing them once.
- You Can't Fight Fate: Rintaro can change the cause, but can never change the effect.
- You Fail Biology Forever: Ruko thinks that if a baby's mother eats lots of vegetables, the baby will be born female. He's right.
- You Have Failed Me...: After Moeka helps Rintaro track down FB, Braun executes her for betraying him.
- You Have Outlived Your Usefulness: The Fate of all Rounder members. After their mission, they are supposed to commit suicide to hide the mission's secret In one timeline, Braun also kills Moeka for similar reasons, and, shortly after, himself.
- Younger Than They Look: Both Okabe and Hashida are supposed to be 18, but look like they're closer to their late 20's. Their tall stature and Okabe's lab coat may have something to do with it. And even though she's like an Adult Child, Mayuri still does not look like a 16-year old.