At first a 3-part OVA before receiving a full theatrical release, Endless Waltz concluded the Mobile Suit Gundam Wing storyline until the release of Frozen Teardrop.
In the year After Colony 196, the "Eve Wars" (the conflict between Earth and the Colonies) have ended, and both Treize Khushrenada and OZ have passed from existence. The Earth Sphere Unified Nation (ESUN), and a special peacekeeping police force known as the Preventers, rose from the ashes of OZ. Since they figure they will no longer have a role in the post-war era, four of the five Gundam pilots (with Wufei as the lone holdout) put their Gundams on a giant disposal satellite headed for the sun. Peace reigns supreme on Earth and in space.
This peace would not last, though: on the anniversary of the Eve Wars' end, a rebellion occurs on newly-completed colony L3 X-18999. The rebellion, led by seven-year-old Mariemaia Khushrenada (who reveals herself to be Treize's daughter), kidnaps Relena Darlian (now the Vice Foreign Minister of the ESUN) during a diplomatic visit to the colony. As the Gundam pilots investigate further, they discover that Mariemaia's grandfather — Dekim Barton, a former adviser to martyred colony leader Heero Yuy — really controls the rebellion. Dekim plans to use X-18999 to go through with the "original" Operation Meteor note if the ESUN doesn't comply with his demands.
The Gundam pilots must prevent Dekim from seizing power over the ESUN, but two things complicate matters: the pilots don't have their Gundams, and the only one that does — Wufei — has defected to Dekim's side.
Endless Waltz exclusively contains the following tropes:
- Adaptation Expansion: The novelization of Endless Waltz contains much more information than the OVA, incorporating elements from all side stories, including Episode Zero, Blind Target, and Battlefield of Pacifists. Unfortunately, it was only in Japanese.
- Anime Theme Song: "Last Impression" (used in the movie) as well as "White Reflection" (used in the OVA), both by Two-Mix.
- Animation Bump: The animation quality of the Endless Waltz OVA series/movie is far and away much better than that of the series.
- An Asskicking Christmas: The Battle of Brussels - most of the Gundam pilots plus Noin and Zechs fighting off hundreds of Serpent Mobile Suits. Plus, Heero and Wufei duking it out in orbit.
- Armor-Piercing Question:
- "How many more people must we kill? How many more times must I kill that girl and her dog?"
- After Heero fires his buster rifle at Mariemaia's supposedly secure shelter, she declares "What a miserable person! He-he's not gonna be able to achieve anything!" In response, Relena asks her "Are you afraid, Mariemaia?" She has no answer for that.
- Back from the Dead:Zechs
- Bait-and-Switch Gunshot: As Dekim was about to shoot Relena, Lady Une quickly draws her own pistol at Dekim. A gunshot is heard, and Dekim falls over dead, shot by one of his own men.
- The Atoner: It is revealed that Heero became this after accidentally killing a little girl he had befriended, to the point where he believed Redemption Equals Death.
- Belated Backstory: The background of the Gundam pilots, via flashbacks.
- Broad Strokes: infamously, this movie featured completely redesigned Gundams even in flashbacks. There have been some manga and novels that attempted to explain the change, usually just settling for an upgrade that happened after the end of the series even if the flashbacks say otherwise. In any case all of the major story events of the series are events of the past.
- Though given the popularity of the new designs, some fans are okay with it being a simple Retcon.
- The redesigns are now canonical. To address this, Hajime Katoki also redesigned the 'first stage' Gundams featured in the show. The manga Glory of the Defeated is a basic retelling of the series with Katoki's designs substituting for Okawara's.
- Though a few additions in Glory of the Defeated have made things even more complicated: the TV version of Wing Zero appears in the manga as Wing Gundam Proto Zero, a prototype of Wing Zero created by Quatre based on the Gundam Scientists' blueprints. It was later heavily damaged and modified into the Endless Waltz version, and prior to the Eve Wars, it was completed, gaining a shield and the transforming ability of the TV version. A few elements of the TV version also made it into the EW Gundams, like the Deathscythe Hell's twin beam scythe and the Altron's tail cannon.
- Butt-Monkey: Duo, in a rare Gundam moment that's actually Played for Laughs.
- Call-Back: Remember that destroyed city in the first opening of Gundam Wing? Heero destroyed it by accident.
- Christmas Episode: The whole OVA take place on Christmas Eve.
- Colony Drop: What the original Operation Meteor turned out to be; the Barton Foundation planned to drop all the colonies onto Earth, and then use the Gundams to take over the world in the resulting chaos. The Mariemaia Army sought to enact the original Operation Meteor by dropping Colony X-18999 onto Earth.
- Confronting Your Imposter: Averted, the novelization explains that Trowa didn't use the name "Trowa Barton" when infiltrating the Mariemaia Army at all. Doubles as Continuity Nod, since the pseudonym he chose was "Ralph Kurt", a character from the side story manga "Blind Target".
- Dark Is Not Evil: Compared to the Mariemaia Army, the Preventers in general don darker uniforms and outfits. But they're otherwise the good guys.
- Dead Person Impersonation: As it turns out, Trowa isn't really Trowa. The real Trowa was a Jerk Ass perfectly willing to go through with the original Operation Meteor, but took a bullet in the back from a more conscientious technician who had family on Earth; the Trowa we know then took over his name (since he apparently didn't have one before) as well as the Gundam Heavyarms he was to use for the operation.
- Death Seeker: The novelization makes it explicitly clear that Heero became this after he accidentally killed that little girl, which explains a lot of his Early Installment Weirdness from the original series, like jumping off a cliff without pulling his parachute cord, and trying to blow himself up the moment somebody sees him (according to the novel, he put the bomb in the suit himself, but Doctor J found it and disarmed it).
- Demoted to Extra: Hilde only appeared (alongside Duo) in the closing credits of the final OAV and the movie, presumably to show that she survived the Eve Wars.
- Deus ex Machina: No explanation is given for how Zechs survived a point-blank reactor explosion at the end of the previous season or where he got a new Tallgeese from. He just shows up in Lady Une's office and asks for a Preventer's callsign and authorization to deploy against X-18999 after having been presumed dead for a year.
- Deus Exit Machina: Four of the five Gundams are en route to the sun, and Quatre (with the Maganac Corps) spends a good portion of the movie on a mission to retrieve them.
- Does This Remind You of Anything?: Relena gets drugged, falling asleep while several older men watch her, all with evil smiles on their faces. Anyone else getting bad vibes in that scene?
- Do Not Adjust Your Set: Done twice; first by Mariemaia, and later, by Relena.
- Double Reverse Quadruple Agent: Trowa. See Reverse Mole.
- Empathy Doll Shot: In Heero's flashback, after he destroyed an Alliance base, a teddy bear is shown being burned inside one of the buildings. It turns out that the teddy bear belong to a little girl (and her dog) he met before his mission.
- Expy: In addition to Mariemaia being one of Mineva Zabi, the Preventers are reminiscent of Londo Bell.
- Extremely Short Time Span: The entire film/OVA takes place over the course of about a week (For comparison, the original series takes place over the course of a year, beginning shortly before Relena's birthday and ending shortly before her next one). If it wasn't for the mention of how much time it would take for Quatre to chase down the satellite with the Gundams on it and bring it back, one might think the time span was even shorter.
- Even Mooks Have Loved Ones: You said that Trowa Barton is not Trowa Barton? Eh, nevermind.
- Fighting Fingerprint: Duo recognizes he's fighting Trowa when he recognizes his tactic of excessively firing all of his weapons at him.
- Freeze-Frame Bonus: Casual viewers can be forgiven for not noticing that the Heavyarms was wearing Trowa's clown half-mask, since most shots of the Gundam are from a long distance and the Heavyarms' face is only closely seen for a half-second.
- George Lucas Altered Version: The movie version actually adds about 20 minutes of additional footage compared to the three episodes of the original. This generally fleshes out the story and characters, adds more action (especially in the climax) and makes the pacing more appropriate for a feature-length movie rather than a three-episode compilation.
- Grand Theft Prototype: The modified Operation Meteor became this once the true nature of the original operation was revealed. Duo and Trowa replaced the original pilots for Deathscythe and Heavyarms, Duo by a typical Gundamjack and Trowa taking over for the intended pilot after he died. Heero and Quetra were instructed by their scientists to disobey the original operation on purpose. Wufei chose to go against the plan on his own.
- Also, in Endless Waltz, after arriving on Colony X-18999, Heero and Duo stole two Leos and engaged in battle with Wufei (piloting Altron) and Trowa (piloting Serpent), respectively.
- Face–Heel Turn: Wufei declined to have his Gundam disposed of, and joined the Mariemaia Army, feeling that warriors like him are being cast aside in a changing world.
- Heel Realization: Wufei had one during his duel with Heero, as Heero's words brought back flashbacks of him seeing the self-destruction of his home colony.
- Heroic Bystander: The nameless soldier who shoots Dekim Barton. The novelization does at least give him a name.
- The people who stand up to the Mariemaia Army.
- History Repeats: The central theme of the entire story: as long as humanity exists, war will exist as well. Though Relena believes that humanity can still achieve true pacifism one day, even if they have to fight to obtain it.
- In the novel and the manga, Lady Une tried to deploy the Virgo III from Vulkanus (the Mobile Doll plant from Battlefield of Pacifists) against the Mariemaia Army, but was stopped by Zechs, who told her that doing this would make them exactly the same as the OZ of the past, Une agreed and ordered the Preventers to continue the dismantlement of the Vulkanus.
- I Have Your Wife: A variant. Once Dekim realizes Heero will be able to destroy the Brussels presidential bunker, he tries to get Heero to stop by shouting that Relena is in the bunker with them. It didn't work. Both Heero and Relena knew this had to be done to achieve peace.
- Improbable Age: Mariemaia. If Episode Zero is to be taken as canon, she's 8 years old. Her voice actor sounds a little too old, but the complexity of her lines, and the rather haughty delivery in the dub, feels way beyond her years (even if she is the child of Magnificent Bastard Treize Khushrenada. Then again, Mariemaia was very much manipulated by her grandfather, Smug Snake Dekim Barton.
She's an expy of Mineva Zabi from Zeta Gundam and Gundam ZZ. The difference is that Haman Khan was using borderline mind control on Mineva to make her give her complex speeches, while, Newtype powers not existing in Wing, Mariemaia just has to be a "really" fast learner.
- Merchandise-Driven: See Broad Strokes. All of the Gundams were redesigned obviously with the intent that they could be sold as new models. This is because most of the revenue for Gundam-related content comes from model kit sales.
- Milestone Celebration: The theatrical release was in celebration of Gundam's 20th anniversary. Funnily enough, in the manga, Duo sports a baseball cap for the very same reason.
- Mook–Face Turn: A Mariemeia soldier shoots Dekim Barton after Dekim shoots Mariemaia and says that he can find a replacement. He then apologizes that Dekim had made them betray Treize's ideals.
- My Fist Forgives You: An inversion. When Heero, Duo and Trowa are in the colony control room with Mariemaia soldiers, Heero asks Duo to hit him... then returns with a punch to the gut that knocks the wind out of him so Trowa can pretend to take him prisoner and preserve his cover. In effect, Heero explains, he let Duo get in his revenge shot first.
- Necessary Evil: Relena seems to view the existence and necessity of the Preventers as this. Even in a world without conflict, there would still be battles, with the Preventers stepping in to keep the peace.
- No, Mr. Bond, I Expect You to Dine: Relena, when held hostage by the Barton clan.
- Non-Lethal K.O.: during the final battle, Zechs, Noin, Duo, Trowa and Quatre take on Mariemaia's Serpent army, incapacitating the suits but not killing the pilots.
- Oh, Crap!: Mariemaia is the poster child for this at the end of Endless Waltz when she tries to call Heero's bluff:Heero: Your shelter is secure, is it?
Mariemaia: Of course it is! See for yourself just how powerless you are!
Heero: Roger that.
- Protected by a Child: Poor, poor Mariemaia. Well, at least she survived.
- Putting on the Reich: The Mariemaia Army uniforms are very reminiscent of Nazi era uniforms. The pilots wear a get-up modeled on the Hitler Youth uniforms. Regular Mariemaia grunts get bright pink Reich uniforms. Even the Preventers' dark uniforms on the ESUN side bear some stylings reminiscent of the Reich.
- Recap Episode: The Endless Waltz box set comes with a four-episode OVA entitled "Operation Meteor" which consists almost entirely of footage from the original series to present character profiles of the pilots, Zechs, Relena, Une and Trieze, with some extra voice-overs.
- Reverse Mole: Trowa joins the Mariemaia Army undercover. It was short-lived, however; as soon as he tries to assassinate Dekim, Wufei shows up holding a sword to his neck. He then joined the Maiemeia army for real, only to defect when Duo appears. He just wants information, after all.
- Renegade Splinter Faction: It turns out the Gundam pilots were this to the Barton Foundation. Operation Meteor was originally meant to be the first steps for Barton's conquest of Earth. Uneasy with the potential two billion casualties, the scientists and pilots decide to ignore their orders, and focus their attacks on OZ.
- Rule of Three: It takes 3 shots from the Wing Zero's buster rifle to breach the Brussels presidential bunker. Of course, it also turns out that's all that the Wing Zero can handle firing off before its badly-battered frame falls apart.
- Slipping a Mickey: Relena's tea is drugged at a meeting concerning the L3 colonies, and she is soon being held hostage by the Mariemaia faction.
- Smug Snake: Dekim Barton.
- Symbolic Wings: Wing Zero's upgraded wings are birdlike, whereas Deathscythe Hell's cloak reveals batlike wings, furthering their respective themes.
- Technical Pacifist/Martial Pacifist: The Preventers, or at least that's the idea behind their existence. Relena and her ESUN supporters knew that even in a world without conflict, an armed presence would still have to step in to prevent potential trouble from boiling into another war. It's also described as a compromise between Relena's supporters and more conservative political parties to keep militarism in check.
- Tempting Fate: "See for yourself just how powerless you are!" Really, Meriemeia? You're telling that to a pilot of the mecha which, because of its presence in the battlefield, changed the tide of the Eve Wars, and that's your response? You're just lucky that he No-Selled your shelter defense. No, wait. You're lucky because Relena is there.
- Thou Shalt Not Kill: The Gundam Pilots decide to spare the Serpents' pilots and not kill anyone if they can help it, so as a result they aim to disable and not destroy them.
- Title Drop: See above quote.
- Together in Death: Both the manga and the novel make it clear that not only did Heero plan to destroy the shelter with Relena still inside, he also intended to kill himself after so she won't be alone. Fortunately, it never came to that.
- What the Hell, Hero?: The battle between Wufei and Heero seems to be also an argument of who deserves this trope more. Wufei for betraying the Gundam Pilots and keeping war going or Heero for living in a peaceful world at the cost of both the soldier's lives and their now perceived uselessness.
- What Measure Is a Mook?: Invoked, Defied, and Conversed with Wufei, who joins up with Dekim because he believes the current worldwide peace is a lie built on the deaths of soldiers, whom he feels were discarded like tools. Deconstructed and Reconstructed in his conflict with Heero.
- "Where Are They Now?" Epilogue:
- Duo, together with Hilde, is now running a junkshop.
- Trowa returns to Catherine Bloom and the circus troupe.
- Quatre, reunited with the Maganac Corps, helps in the restoration of the colonies.
- Wufei joins the Preventers as Sally's partner.
- Zechs and Noin take off to Mars for a terraformation project.
- Lady Une takes Mariemaia to visit the grave of Treize Khrushinada.
- Heero and Relena's ending is different from the OVA and the film (the others have at least consistency): the OVA shows Relena at a press conference as Heero watches over her from the shadows, while the film shows the two of them in different places at once. The Manga adaptation shows a THIRD ending where Heero becomes Relena's bodyguard. The Novelization tried to bridge the gap between OVA and Movie by saying that Heero watches over Relena, and then leaves.
- Worf Had the Flu: From the damage it sustained during its duel with the Nataku (and subsequent re-entry through the atmosphere), the Wing Zero appears above the Brussels presidential bunker, only with enough strength to fire its Twin Buster Rifle three times, with the third shot's recoil completely obliterating the Gundam.
- A variant occurs with the other Gundams' last stand. It's stated outright that if they didn't care about saving the enemy pilots, it would have been a Curb-Stomp Battle in their favor. However, since they're fighting carefully to make sure all of the enemy pilots survive, their Gundams get worn down by pure attrition from the prolonged battle.