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Riddle for the Ages

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It's been 25 years since it happened, and he still doesn't know how that pineapple ended up on his nightstand.note 

"What I couldn't work out was how he managed to make another man pregnant. I guess we'd never know. So, just to restate, that is something we'll never know; you're not going to find out later."
Rick Dagless, Garth Marenghis Darkplace

It is the nature of mysteries that people want to find answers, and since fiction is in the business of giving people what they want, just about any mystery introduced in a story is going to be resolved. Important character gets murdered? We're gonna find out who the culprit was. The Eiffel Tower disappears? We're gonna find out where it went and why. Someone blacks out and wakes up three days later wearing antique samurai armor and a pink cowboy hat? We're gonna find out what led them to that state of affairs. While mysteries might sometimes be left unanswered inadvertently (such as a series being abruptly canceled, or the writers simply forgetting the mystery exists), if the people in charge know what they're doing, for every mystery introduced there's going to be an answer introduced somewhere down the line.


Except when there's not. Sometimes writers will create a mystery but never have any intent of actually giving us an answer. Bob will wake up one day to find $10,000,000 has appeared in his bank account, or Alice will discover someone's rearranged all her furniture while she was out. They might brush these matters aside cavalierly, or they might become obsessed with discovering the truth, but eventually they come to realize that, if they're ever going to get an answer, it's not going to be any time soon, and write off their respective mysteries as "one of those things".

This might be done for comedic effect, as part of a Mind Screw, or just to reflect reality. After all, how many of us have had something weird happen in our lives but never discovered the "why" behind it all? Like all tropes, this sort of mystery can be used to tell really good or really horrible stories depending on the writers' skills, though if you're introducing an answerless mystery, it's generally considered good form to let your audience know they're not getting an answer. It's not quite fair to present viewers a mystery, suspects, and clues that clearly have some sort of resolution, if only in the author's head, but never say what it is. Make it clear that you're not going to let people in on an important secret that you or someone on the production staff knows the answer to, and years might go by and people will still be asking you, "Why did X commit Y on Z?"


Please note that, to keep the examples section from getting bogged down, we should list only cases where a mystery is left unanswered and, either through context within the story or via Word of God, we know it was never meant to receive an answer. Without either of these things, it should be assumed that the writers meant to answer the mystery, but have not yet gotten around to doing so.

Super Trope of Maybe Magic, Maybe Mundane. Cousin of the Cryptic Background Reference (they both add to the sense of a larger universe by leaving unexplained mysteries). See The Un-Reveal. Compare Noodle Incident, The Unsolved Mystery, What Happened to the Mouse?, Missing Secret, and some Big Lipped Alligators. A common feature of a Mockstery Tale, and may lead to Wild Mass Guessing and Epileptic Trees.

Not to be confused with A Riddle Wrapped in a Mystery Inside an Enigma.


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    Anime & Manga 
  • In Code Geass, CC tells Lelouch her real name, but the sound is muted the exact moment she says it, preventing the audience from finding out. The same happens when Lelouch repeats it to her.
  • Did Bradley from Fullmetal Alchemist love his wife? He openly admits that he considers himself superior to humanity, but he also says that his wife was the one thing about his life that he himself chose. As he dies, he says that he has no message for her because that's the relationship of a king and his wife.
  • 7 Seeds: The Ryugu Shelter arc has a mangaka in its mist, who works on the manga Wonderful Q. The driving question of the manga is the protagonist looking for the answer of "What is 'Q'?". The final chapter of the arc shows Mark picking up a page of the final chapter, revealing that the protagonist had found the answer, though the reader is never shown. So... what exactly is Q?
  • In Maison Ikkoku, after fourteen volumes and some six years of in-universe time, neither the readers nor the other characters have any real idea of Mr. Yotsuya does for a living...or, indeed, any knowledge of his life outside the apartment. His one and only day in the limelight is devoted to him evading the other characters' attempts to figure out what he does all day.
  • Pokémon:
    • Nurse Joy and Officer Jenny. Maybe they are simply just the female members of extended families who happen to look exactly alike and who all choose the same career, but fans have to wonder. All we know is it's prime Fanfic Fuel.
    • What happened between Brock and Prof. Ivy, and why does Brock flatly refuse to talk about it?
    • What was in the GS Ball? Word of God says that it was supposed to be a Celebi, but that got scrapped when they decided to use Celebi in Pokémon 4Ever, so the question remains unanswered.
    • Who is Ash's father? Word of God is that he's alive and that they would bring him in if he would be important to Ash's development.
    • Who are Tobias' (at least) four other Pokémon besides Darkrai & Latios? Common joke answers within the fandom are "four Magikarp" or "four Bidoof".
      • And on the subject of Tobias, how did he get his hands on Legendary Pokemon, and how was he allowed to use them in the League without being punished?
    • One pertaining to the ending of Pokémon Heroes: Was it Latias that kissed Ash, or Bianca?
    • Why is Cilan so afraid of Purrloin?
    • Everything about the backstory of Genesect and the Legend Awakened's Mewtwo is this, due to the film explaining nothing beyond the bare basics of Mewtwo's origin in every canon. Don't ask how it was made when its creators seemingly didn't know about the original, either.
    • Clemont and Bonnie's father being a masked vigilante is never explained once. Not even his kids knowing his true identity was enough for them to question his motives.
    • Exactly what is the full story about the Ash-Greninja in the past? The only explanation it has is that it just... appeared out of nowhere and ended the ninja war before disappearing from the face of the planet, but there is absolutely nothing else about it or if it even had a Trainer that (once again) resembled Ash.
    • Where did James get his Weepinbell from that evolved into Victreebell?
    • What is Pikachu's story? How did it get into Professor Oak's lab in the first place?
  • Some questions that Neon Genesis Evangelion leave unanswered:
    • What did Gendo say to Ritsuko before he shot her?
    • Which ending (TV or movie) actually happened? Is the movie ending taking place for real, or is it just what Shinji wanted out of Instrumentality?
    • Whose soul is in Unit-00?
    • Who was responsible for the mysterious blackout in Episode 11 that nearly allowed an Angel to invade?
    • Who killed Kaji? Word of God implied it was just a random SEELE or NERV henchman, presumably ordered to do so by Keel Lorenz.
    • Why did Shinji see a Rei hallucination when he first came to Tokyo-3? And then again after the Assimilation Plot had ended?
    • From whom did Kaworu get his looks? Kaworu and Rei are both angelic souls in human clone bodies. Rei is Lilith's soul in a Yui Ikari clone, while Kaworu has the soul of the angel Adam, whose true form is never seen; it's not known who his prime clone was.
  • Dragon Ball:
    • What was Darkness actually?
    • Dragon Ball Z: The name of Freeza's race, despite several new members of it being introduced in various DBZ-related works, has never been revealed. Dragon Ball Xenoverse, which lets you play as one, called them "Changelings" in the beta stages... but then in the live release they were just called "Freeza's race" in character creation. According to Word of God, apparently there is not an entire race of people as strong as Freeza. His family is an abnormally strong mutant offshoot of said race and are much more powerful/evil than its normal members.
    • From Dragon Ball Z: The Tree of Might, how did Turles discover the Tree of Might (a sacred plant that is implied to be from the higher realms) to begin with, let alone how he obtained its seeds and learned how to cultivate and harvest its fruit, is all anyone's guess. Nothing from the manual or Dragon Ball Xenoverse 2 give an answer.
  • In Mobile Suit Gundam SEED, a few episodes after their breakup, Flay wanted to speak to Kira, but he says it will have to wait 'cause he's heading to battle. He promises they'll talk after, but they never get a chance to meet face to face again. We never found out what Flay wanted to say as she wasn't in her usual bitch mood and sounded apologetic when she approached Kira.
  • In the original Mobile Suit Gundam:
    • It's never made entirely clear whether or not the Zabi family really did assassinate Char's dad, Zeon Deikun. The official story is he died of a heart attack (The Origin does show him to have been very stressed and high-strung at the time) but Char himself and most other people who mention his death treat the assassination angle as an Open Secret. Mobile Suit Gundam: The Origin, however, implies that the assassination theory might have been cooked up by Deikun's Old Retainer Jinba Ral both to discredit the Zabi family and to mold Char into a Tyke Bomb against them. In the end, it's one of those enduring mysteries that conspiracy nuts of the Universal Century will debate for centuries, until the ∀ Gundam kills them all.
    • In the "Tomino Memo" (said to be Yoshiyuki Tomino's original 50-episode plan for Mobile Suit Gundam), Dewgin Zabi meets the White Base crew and, recognizing Sayla as Deikun's daughter Artesia, begs her forgiveness for having killed her father and perverted his dream. Of course, one might not buy the whole "original plan" idea; Gundam Sousei puts forth the idea that it's nonsense Tomino threw together to tempt the sponsors so they would fund the compilation movie trilogy.
  • Played with in one of the prequels of Legend of Galactic Heroes, where Yang Wen-li investigated a mysterious weekly correspondence which asserted that the Alliance war hero Bruce Ashbey was murdered and not killed in action as popularly assumed. He ended up uncovering circumstantial evidence that Ashbey was the recipient of leaked intelligence provided by a massive secret espionage network established by a disaffected Imperial noble. The actual existence of such a network was however never revealed in the story and Yang himself asserted that his hypothesis might never be proven unless both the Alliance and the Empire ceased to exist.
  • JoJo's Bizarre Adventure: Diamond is Unbreakable:
    • Is Mikitaka an alien or just a weird human?
    • The identity of Josuke's mysterious savior who inspired him to takes his hairstyle. Some fans speculate that he was supposed to be Josuke himself who traveled back in time for some reasons but that plot point was later scrapped.
  • Parasyte: Thematic implications aside, there is never a true explanation as to what the parasites are exactly, where they come from, or what purpose they serve. Similarly, why certain humans like Kana and Uragami could sense the aliens is also glossed over.
  • FLCL hardly explains anything about the backstory: what makes Naota such a perfect vehicle for "N.O. channels"? How did Medical Mechanica get their hands on Atomsk in the first place? Was Medical Mechanica really planning to bulldoze the Earth with a giant steam iron as part of some mind-control scheme, or was that just a wild guess by Amarao? And who exactly is Haruko Haruhara?
  • Yu-Gi-Oh!:
    • Who won the Duel between Yugi and Joey at the very end of the Battle City arc? He was dueling to get his Red Eyes Black Dragon back, and he's later shown with it, implying he won, but that's another trope entirely. Also, at the end of Yu-Gi-Oh! GX, who won the final duel: Yugi or Jaden?
    • What is the Kaiba brothers' birth surname, and why did they keep the name of their abusive stepfather even after his death?
  • Fireworks Should We See It From The Side Or The Bottom 2017: The exact origins and workings of the bauble are left as a mystery. There is all of one hint - when Nazuna talks about her missing father while in the train, the film suddenly shows a drowned man in the sea holding onto an identical bauble - but what that really means is left up to interpretation.
  • In Berserk, perhaps the most enigmatic character is the Beast of Darkness, a sinister Hellhound that lives inside Guts' mind and urges him to do terrible things such as rape and murder his own Love Interest. To date, the author has never made it clear whether the Beast is a distinct being, merely a visual metaphor for Guts' own repressed dark impulses, or something else entirely.
  • Bleach:
    • Why are all of the hollows and arrancar of Hueco Mundo inexplicably Spanish?
    • How did Soul Society thwart Yhwach's invasion 1000 years ago? Given his reaction to Yamamoto's bankai, it's implied that Yamamoto defeated him in the past without resorting to it. How he managed to do that despite the Quincy emperor's Story-Breaker Power is anyone's guess.
    • What does Ichigo's true bankai do? Considering that the series was axed by Shueisha right after Yhwach preemptively destroyed Tensa Zangetsu when Ichigo released it and the manga had to rush to the ending, it's unlikely we'll ever get to see what it's capable of beyond its signature Getsuga Tensho and why Yhwach decided it was such a threat.
  • In Dallos, the titular machine is a big question mark from start to finish. What it is, who made it, and why it was made are never explained.
  • One Piece has the mysterious entities living in the Florian Triangle. Although some of the disappearances that have happened in the Florian Triangle can be attributed to Moriah's scheme, the truth is that ships have been disappearing mysteriously in it for a long time before he came on his ship, Thriller Bark, ten years before the series. This mystery is confirmed by an unknown ominous entity larger than Thriller Bark. It was barely seen by Lola through the fog.
  • Umi no Misaki never explains the Human Sacrifice tradition the island has. The Dragon God is real, but he doesn't condone it, so why is it done in his name? The people doing the sacrificing don't seem to like it either.
  • Death Note: Did Misa Misa really commit suicide at the end of the series? And, in the manga only, the heck was up with that cult at the end?
  • Puella Magi Madoka Magica: Did Sayaka kill the two men on the train for badmouthing their girlfriends? While other Words Of God have given an answer, Gen Urobuchi, the writer of the series, has said that it's supposed to be ambiguous.

  • In Joyce Grenfell's "Nursery School" routines, her Catch-Phrase was "George, don't do that". We never learned what George was actually doing.

    Comic Books 
  • The identity of The Joker, Trope Namer for Multiple-Choice Past.
  • Seen in Tintin's adventure Tintin: Land of Black Gold: Captain Haddock shows up to rescue Tintin even though he was half a world away, and never gets around to explaining how that was possible. He's interrupted right after "It's both very simple and very complicated." or "Well, you see, it's like this..." in the English translation.
    • The lack of explanation for Haddock's appearance is actually a meta joke: the original version of Land of Black Gold was initially serialized in a newspaper in 1939 and 1940, but after Germany occupied Belgium in 1940, Hergé thought that the comic would not pass the German censors because of its political nature, so the publication of Land of Black Gold was stopped mid-story. At this point Captain Haddock hadn't yet been introduced in Tintin, so naturally he didn't appear in Land of Black Gold either. Several other Tintin stories were published before Hergé decided to redraw Land of Black Gold in 1948, and in these intervening stories Haddock had become the most significant character in the series besides Tintin himself. Thus it would've been odd if Haddock had been left out of the new version of Land of Black Gold, but on the other hand he didn't really belong to a story that had been scripted before he even existed. This is the reason why Haddock is virtually absent from the story until the very end, and why there's no explanation for his sudden appearance. The lack of explanation is Hergé's comment on Haddock "invading" a story he wasn't originally a part of. So there is a solution to the mystery on a meta level, but not in the text.
  • Uderzo, the author/artist of Asterix has said that two things will never be revealed about the Astérix universe: what are the exact contents of the Magic Potion (only mistletoe and oil/beetroot juice have been revealed) and what is the name of Geriatrix's wife (even Asterix calls her "Mrs. Geriatrix").
  • In Gaston Lagaffe, what are those contracts about that M. De Mesmaeker is always trying to sign?
  • In Y: The Last Man, no one knows what caused the Gendercide. While several theories are made in the story, and Word of God confirms that one of those theories is true, he refuses to say which one. Yorick even invokes Fan-Disliked Explanation in-universe after an encounter with a Mad Scientist.
  • The Dan Dare story "The Red Moon Mystery" concerns an asteroid-like object that can move freely in space to attack other planets despite being home to nothing but some bee-like insects. Dan and co. are ultimately forced to destroy it before they can discover how any of this works.
  • Deadpool: Is the titular Merc with a Mouth really Wade Wilson or not? Is T-Ray the real Wade Wilson like he says or is he just lying or crazy? Did a guy named Wade Wilson ever really exist to begin with? Nobody knows for certain and probably never will. At the very least, Deadpool himself seems pretty sure that he's the real Wade Wilson but this is Deadpool...
  • Did Cerebus go to Heaven or Hell at the end of Cerebus the Aardvark? Cerebus seems certain that it's Hell but it's not explicitly stated.
  • In The Walking Dead it's never revealed what started the zombie outbreak, because the interaction between the characters is more important.note 
  • Judge Dredd: What does Judge Dredd look like? It's an enduring tradition of the comic not to reveal the face behind the helmet. Fans never forgave Sylvester Stallone for taking the helmet off in Judge Dredd, and Karl Urban made a point of never removing it when Dredd came about.
  • ElfQuest: Why did Olbar the Mountain Tall take away his brother's name? And what was he called, anyway?
  • Final Crisis: Who was the mysterious apelike man who helped Nix Uotan regain his Monitor powers? This is the one question this Mind Screw of a story leaves totally unanswered, and the most popular guesses at the time were Detective Chimp, the New God Himon placed into an ape body by Darkseid's forces, and the typewriter-using monkey from Morrison's Animal Man.
  • 100 Bullets:
    • What other country did the Trust order the Minutemen to take over? The Minutemen's refusal to do this kicks off the entire plot, but the reader never learns what country it was.
    • What was the exact significance of the Morte dil Cesare painting, and why did Echo Memoria want it so badly? Echo quite literally takes these secrets to her grave - her body is wrapped in the painting and both sunk into a swamp.
    • How did Remi Rome kill Mia Simone? Mia dies when she falls out a high window onto a car, but Remi's already at the bottom of the building talking to Cole, so he can't have pushed her. Remi declines to answer when Cole asks.
    • Who was the mysterious man in glasses seen at the end of volume 10, and was he really going to murder that homeless couple he gave a ride to?
  • In the Disney Ducks Comic Universe, whatever happened to Della Duck, sister of Donald and mother of Huey, Dewey, and Louie? A special Dutch comic produced for the 80th anniversary of the triplets' creation stated that she was a NASA test pilot who got lost in space, but fan reaction was mixed and as the Duckverse has multiple continuities this isn't necessarily the one "true" explanation (especially as the story contradicts well-known canon: Della is shown passing the nephews to Donald while they are babies/infants, except Donald clearly adopted the children as they were at least older than four). An unpublished story by Don Rosa implied that the triplets's father was from Tra-la-la and had returned there after his wife's disappearance.
    • Also, what happened to her husband. And also, what happened to Donald's parents. Even when Donald met Mathilda again in Don Rosa's A Letter From Home, they don't even mention Hortense, Donald's mother and Mathilda's sister. In fact, Donald has only ever interacted with Hortense when he saw her as an infant in Scrooge's dream.
    • In The Life and Times of Scrooge McDuck, did Scrooge really single-handedly destroy Soapy Slick's riverboat, or did he - as he himself claims - simply use a conveniently-timed boiler explosion to escape, with the tale being exaggerated over the years? Don Rosa has stated that he will never answer this question, as he meant the scene to be a nod to the various tall tales and semi-legendary figures of the 19th century American frontier such as Pecos Bill.
  • The Sandman: who killed the first Despair and why? All we know is that it will take the rest of the life of the universe for him to finish dying and that he was entirely justified in killing her.
  • "Wolf Bait" from The Haunt of Fear. We will never know which passenger of the sleigh was chosen by the others to throw to the wolves.

    Comic Strips 
  • Calvin and Hobbes:
    • What was the Noodle Incident?
    • What is Calvin's family name? And what are his parents' names?
    • What is the subject matter of Hamster Huey and the Gooey Kablooie?
    • What, precisely, is Hobbes—a stuffed animal or a living creature? If he is the latter, why is Calvin the only one who sees it?
    • These are all questions that Bill Watterson has specifically refused to answer, either feeling the answers unimportant (as in the case with the characters' full names), or more satisfying if left up to the reader to decide (as is the case with Hobbes's true nature).
    • Calvin invokes it intentionally when he refuses to tell what he brought to "Show and Tell".
      It's a mystery that will haunt you all your miserable lives! You'll never, EVER know what I brought! You can beg and plead, but I'll never end your torment! I'll carry my secret to the grave! It's the show and tell that was never shown or told! (Evil Laugh)
  • Sally Forth: What exactly does Sally Forth's husband do for a living? Even they aren't sure.
  • Peanuts:
    • Did Charlie Brown manage to kick the football this one time?
    • What does the little red-haired girl look like? However, she is shown in the TV cartoons.
    • What do the parents and teachers look like? There were in fact some cartoons that depicted adults but even then, the parents and teachers were never specifically shown.
    • What does the cat next door look like? Word of God said this is because he's not good at drawing cats.
  • When a Dilbert story arc involved the title character getting a girlfriend, the issue arose amongst the readers of whether Dilbert might actually "score" with her. Since sex wasn't something that could be openly discussed in a newspaper comic, Scott Adams told his readers that should Dilbert get lucky, his perpetually upturned tie would be drawn hanging flat. The flat tie strip did eventually come, but Adams still wrote the comic in such a way that it wasn't clear if Dilbert had had sex or not.
    • In another strip that introduced Antina, the antithesis to Dilbert's coworker Tina, Dilbert's tie is flat in the last panel. Even Adams doesn't know why.
  • Garfield:
  • The Boondocks: Where are Huey and Riley's parents?

    Films — Animation 

    Films — Live-Action 
  • Played for laughs in The Adventures of Buckaroo Banzai Across the 8th Dimension:
    New Jersey: Why is there a watermelon there?
    Reno: I'll tell you later.
  • American Animals: We watch Warren go to the Netherlands to meet a fence at a bar before The Heist, but after the botched heist, the other members wonder if he'd made the whole thing up. We see a second version of the events in which Warren does not get on the plane and instead goes to an American bar that looks exactly like the Dutch bar. The real Warren, who provides commentary throughout the film along with the rest of the real heist members, simply says, "I guess you'll just have to take my word for it."
  • In Arrival it is never specified what, exactly, humanity did that would warrant the Heptapods going back in time to ensure the survival of humanity so that humanity can in turn save the Heptapods 3000 years in the future.
  • Back to the Future: What does the DeLorean's stainless steel construction do to the flux dispersal? Doc was going to explain before he and Marty hurriedly moved to accommodate Einstein's arrival through time.
  • Bad Times at the El Royale has the identity of the person on the incriminating film that the eponymous hotel keeps for blackmail purposes, as well as what they were doing when filmed. All we're told is that the person is now dead and they were well respected in life, thus the film being released would result in a major scandal. The last two surviving characters throw it into the fire at the end, never having looked at it themselves.
  • Blade Runner never actually gives us a straight answer as to if Deckard is human or Replicant. Blade Runner 2049, if anything, muddies the issue even more.
  • Blind Chance has no real explanation of WHY Witek lives through the story three times - if he really does. The events simply restart on their own accord, each time with minor changes at the train station, which are also left unexplained. There is also his wife sensing something wrong about the flight and asking him not to go.
  • Want to hear a dirty joke? "A gorgeous blonde lady walks into a bar, naked, with a poodle under one arm and two foot salami in the other. She places the poodle on the table, and the bartender says, 'I suppose you won't be needing a drink?' And the lady replies -" unfortunately, fans of The Breakfast Club will likely never know the punchline to this joke, as Bender falls through the vent he's climbing through before he can finish it.
  • In Caché, we never find out who sent the tapes, or why. There are many clues, but no answers.
  • In the Disney film Candleshoe, Jodie Foster's character is hired by a con artist to pose as the Long-Lost Relative of an English noblewoman. At the end of the film, it's suggested that Foster's character might actually have been the person she was impersonating, but we don't find out for sure.
  • The Citadel is about Dr. Manson, an idealistic young doctor who saves his patient with a technically forbidden treatment—namely, taking her to an expert who isn't actually a medical doctor and allowing the expert to perform surgery. The treatment works and saves the patient, but Dr. Manson is still brought up before a review board that has the power to strip him of his license. Dr. Manson gives a Rousing Speech to the review board in which he decries British medicine's unwillingness to listen to new ideas. Then he storms out, and the film ends. We never do find out if Dr. Manson got to keep his license.
  • Count Yorga: Did Yorga really turn himself into a vampire through occult magic or just a victim of a previous vampire. Also what made him want to come to Los Angelos after living and spreading his vampirism in Bulgria for so long.
  • Crank: High Voltage: What was in Johnny Vang's cooler that disgusted Chevy so much?
  • The Dark Knight:
    • What is the backstory of the Joker? It's even a specific trope.
    • More importantly what happened to him after he was arrested. Due to Heath Ledger's death, his planned return was written out in The Dark Knight Rises and he isn't even mentioned in the movie. The novelization does add in that he was the only recipient in the abandoned Arkham Asylum during the events but doesn't confirm if he's still there or escaped during Bane's takeover of the city, leaving his fate in the air.
  • In The Day the Earth Stood Still (1951), Klatuu tells Helen that if he is killed, Gort will destroy the Earth, and to stop him, she must use the code word "Klaatu Barada Nikto". She successfully does so, but exactly what the phrase means (obviously, it's something in Klatuu's language) has never been truly revealed. Word of God is actually contradictory on this. The film's director, Robert Wise, related a story he had with Edmund North, the screenplay writer, saying North told him, "Well, it's just something I kind of cooked up. I thought it sounded good." On the other hand, Billy Gray, who played Bobby Benson in the film, said that "barada nikto must mean... save earth". Florence Blaustein, widow of the producer Julian Blaustein, said North had to pass a street called Baroda every day going to work and said, "I think that's how that was born." Film historian Stephan Jay Rubin claimed that in an interview he had with North when he asked the question, "What is the direct translation of Klaatu barada nikto, and Edmund North said to me 'There's hope for earth, if the scientists can be reached'."
  • Detroit: What happened to the starter pistol? We see Carl Cooper fire it at the police as a prank, then get killed as they storm the Algiers motel, but even after a prolonged search, no one is able to locate the starter pistol or any other weapon in the motel. Text at the end states that the starter pistol was never found. This is Truth in Television, as several victims of the Algiers Motel incident claimed that Cooper fired a starter pistol before the police raid, but neither it nor any other weapon was ever found.
  • The Disaster Artist: Where does Tommy Wiseau's money come from? Where did he get his accent? How old is he? These are all questions that have never been definitively answered in real life either, although there have been some pretty decent guesses at the latter two (he was born in Poland and moved to France at a young age before learning English, and around 48 at the time of The Room's filming in 2003).
  • Elizabethtown: Why on God's green Earth was Drew's shoe design recalled? The movie dwells extensively on the aftermath of the recall, and Drew's struggle with depression (at the very beginning of the film suicidal even) courtesy of being pinned as the mastermind of a billion-dollar Epic Fail in the footwear industry, but why the shoe failed is never even so much as hinted at.
  • Eraserhead has a meta example: every single person involved with the film, up to and including David Lynch himself, has declined to comment when asked what the prop used for the mutant baby was made from. This has predictably led to all sorts of grisly speculation, including that the prop was an actual aborted calf fetus.
  • In Fright Night (1985), we never do learn what Billy Cole was, only that he was neither human nor vampire. The novelization shows the heroes are as perplexed about this as the reader. Likewise if that was Evil Ed at the end spying on the protagonists at the end of the movie.
  • Game of Death: None of the surviving materials reveal what is on top of the pagoda. There are many rumors (a scroll, a mirror, another fighter, something supernatural, nothing) but none of these are canon. One can assume that Bruce Lee's intention was that it's unimportant what is on top of it, the quest to the highest level counts.
  • Griff the Invisible: Did Melody really phase through solid matter at the end? Did she actually briefly turn invisible halfway through? Was Griff's cat real?
  • The Hangover: What the hell happened to that chair? And why was the chicken there?
  • The final scene of Inception, in which it is purposefully unclear if Cobb has finally seen his kids or if he is dreaming. Cobb spins a top to test whether or not he is dreaming; if it stops spinning, he is in the real world, but the film invokes a Smash to Black before this happens.
  • James Bond: In Live and Let Die, who, or what, is Baron Samedi, and how did he survive so many things that should've killed him? Is he really the Vodou Loa of death from whom he takes his name? If so, why is he working for a mere mortal drug lord?
  • Krampus ends with the Engel family restored to life after having seemingly all been killed by the eponymous creature the night before, but then we pan out to reveal that Krampus is observing them through a snowglobe, and he has dozens more just like it in his lair. It's never stated whether he's literally holding them prisoner in the snowglobe or if it's simply a scrying device he's using to keep an eye on them - though the tie-in comic suggests the latter.
  • In K-PAX, was prot a delusional savant, or genuinely an extraterrestrial from the planet K-PAX?
  • What's whispered at the end of Lost in Translation? Audio clean-up suggests it's "I won't see you till the next making of Suntory. Go to that man and tell him the truth, okay?" However, this is irrelevant; Sofia Coppola didn't write any lines for the scene, she just told Bill Murray to ad-lib something.
  • In The Maltese Falcon we never do find out what happened to the original. The criminals are pretty sure they just accidentally clued in the guy they stole it from so he set up a decoy.
  • Minority Report: Anderton never gets any answers about who took his son or even if the boy is still alive.
  • Used for purposes of Mind Screw in the French film The Moustache, which also has No Ending. The protagonist may or may not have Ripple Effect-Proof Memory, with someone or something repeatedly changing the world around him. He also may or may not be the only one getting messed with, and it's left uncertain whether he'll ever figure out what's going on and how to end it.
  • Once: Did The Guy come back for The Girl on the bus seen in the film's last shot, or didn't he?
  • Pandorum: What the hell happened to Earth? The characters discover that the Elysium picked up a radio signal claiming that the planet is gone and the crew of the Elysium are the "last of us". It's noted that the colony ship left because Earth was getting overpopulated and polluted, but it certainly didn't seem like the world was literally ending outright. Since the Elysium is light years away and has been out of touch for centuries, the heroes never find out what happened and by the end it's the only mystery that isn't answered.
  • Picnic at Hanging Rock: Why did the girls suddenly wake up, and then walk into the mountain? And more importantly, what happened to the girls and their teacher (who also disappeared) after? While the novel does eventually include an extra chapter explaining the fates of the girls (which arguably would've ruined the film's powerful mystery), the film leaves their fates extremely ambiguous.
  • Pirates of the Caribbean: How did Cotton manage to teach his parrot to talk for him?
  • The contents of the briefcase in Pulp Fiction. Quentin Tarantino originally intended for it to contain diamonds, but he'd already used diamonds as a MacGuffin in Reservoir Dogs, so he nixed that idea (though that hasn't stopped fans from speculating that the Pulp Fiction briefcase contains the Reservoir Dogs diamonds). Samuel L. Jackson, meanwhile, said it contained "two heavy-ass batteries and three lights."
  • In The Quiet Man Mary Kate whispers something to her husband Sean Thorton which gives him a shock. This is also a Real Life mystery, as director John Ford told Maureen O'Hara to whisper something shocking to John Wayne to get that reaction. The three of them never explained what was said... And unless O'Hara mentioned it to someone else for posterity, the secret died with her in 2015.
  • In Ready Player One, the avatar of James Halliday, creator of OASIS, still exists in the virtual world despite the fact that the real Halliday is dead, which shouldn't be possible. Wade asks him why this is at the end, but Halliday simply shrugs and disappears.
  • The contents of the silver case in Ronin. The main characters even demand more money because their employers refuse to tell them anything about it. It's somewhat implied to be a WMD (perhaps a suitcase nuke). After losing it, the IRA makes peace.
  • Star Trek II: The Wrath of Khan: In his Establishing Character Moment, Khan removes his left hand glove, but leaves his right hand glove on through the rest of the film. Fans have always asked director/screenwriter Nicholas Meyer why, but he's never given an answer, often saying "Why do you think he wears it?".
  • Star Wars:
    • The exact name and homeworld of Yoda's species are still unknown. Revealing these facts is one of precisely two things Star Wars Legends authors were forbidden from doing by George Lucas himself. The other was showing how Luke, Han or Leia died. In the new continuity, however, The Force Awakens and The Last Jedi reveal how Han and Luke, respectively, die.
    • What Jawas look like under their hoods. In the EU, they are described as resembling gaunt rodents of some sort, but other sources suggest they are actually pygmy humans or more closely related to their equally mysterious neighbors, the Tusken Raiders (which leads to the possibility the two are both descended from the extinct Kumumgah).
    • On the subject of Tuskens, what they call themselves has also never been revealed. Both "Tusken Raiders" and "Sand People" are names given to them by their enemies.
    • Who or what are the Whills, who are said to be chronicling the entire franchise? An early draft of Revenge of the Sith had Qui-Gon reveal the secret of becoming a Force spirit had been imparted on him by the Whills. Chirrut and Baze from Rogue One are Guardians of the Whills, and the Holy City on Jedha has the Temple of the Whills, implying them to be a religious order of some sort.
  • Street Trash: What is Viper, why does it melt people, and how did it end up in the back of the bar?
  • Upstream Color: Where did the mysterious blue substance come from, and what was the relationship between the Thief and the Sampler?
  • Who Killed Captain Alex?: Who killed Captain Alex? It wasn't the Tiger Mafia's leader, nor any of its members. Even the director didn't know. The fact that the film never answered it is apparently something of a running gag in other Wakaliwood films. It was finally answered in 2016 with the release of Bad Black. Turns out it was the protagonist of that movie, Swaaz, in an incident completely unrelated to the previous film.
  • The Wicker Man (1973): Willow's attempt at seducing Sgt. Howie is never explained. It may be a test of his chastity, since he's intended to be a virgin sacrifice in the end.
    • In mythology, there is often a forking point in the story where a potential victim is given a chance to turn away from his fate if he is insightful enough and open-minded enough to recognize it and accept the opportunity. This makes Sgt. Howie's fate his "own choice" as a result of how he has chosen to live his life and how he has chosen to close his mind.
    • Popular fan speculation is that she felt sorry for him and was trying to offer him an escape clause.

  • Frank R. Stockton's "The Lady or the Tiger?" In the story, a king forces each criminal to choose one of two doors. Behind one is a beautiful maiden that he will instantly marry. Behind the other is a ravenous tiger that will tear him to pieces. One criminal is the lover of the princess, who knows which door leads where. She gestures toward a door, and he opens it, but what does he find? Could the princess bear to see him marry another woman, or would she rather he died? The story caused something of a sensation in the years following its release, with readers clamoring to wring an answer from the author. A common writing assignment in classrooms is to supply an answer to the question. The sequel story, "The Discourager of Hesitancy", doesn't answer the question either.
  • Alice's Adventures in Wonderland:
    • "Why is a raven like a writing desk?" The riddle is never intended to have an answer, prompting many fans throughout the ages to supply their own answers:
      • Sam Loyd's "Because Poe wrote on both" is the most popular answer.
      • "Because the notes for which they are noted are not noted for being musical notes." Sam Loyd again.
      • Stephen King's "The Shining" has a rather good answer for that: "The higher the fewer, of course."
      • Carroll himself eventually supplied his own answer, but only after years of people asking: "Because it can produce a few notes, tho they are very flat; and it is nevar put with the wrong end in front." Note that "nevar" is "raven" spelled backwards.
      • "Because there is a B in both and an N in neither." (Aldous Huxley)
      • "Because it slopes with a flap." (Cyril Pearson)
      • One Two Lumps strip both re-uses the above "Poe wrote on both", and also suggests "Both have inky quills."
      • From Sir Apropos of Nothing, "Because it is only with quills that they truly take flight."
    • Another one: Was Through the Looking Glass Alice's dream, or the Red King's dream?
  • Tolkien's Legendarium has a lot. Some of them are because J. R. R. Tolkien constantly meddled with his lore and didn't come up with a satisfactory answer himself before his death, but some of them were intentional. (The unintentional ones are starred.)
    • What is Tom Bombadil?
    • What other evil creatures, which were worse than the Balrog according to Gandalf, were buried under Khazad-dûm?
    • Who were the Ringwraiths before they received the Nine Rings? We know that three (probably including the Witch-king) were Númenóreans, and that Khamûl (the only Ringwraith to be named anywhere by Tolkien) was an Easterling king. Other than that, nothing.
    • Where did Radagast and the blue wizards go? *
    • What happened to the Entwives?
    • Was Sam allowed to cross the sea to Valinor? According to his relatives, the answer is yes, but no-one actually knows.
    • Where do the souls of dead Men go when they leave the Halls of Mandos?
    • What was the 'First Fall of Man' that Tolkien claims happened before Men arrived in Beleriand?
    • Did Amandil reach Valinor?
    • What is the origin of Ungoliant?
    • What happened to Eluréd and Elurín?
    • Are Maglor and Daeron still wandering around Middle-earth?
  • The Chronicles of Narnia (by Tolkien's pal C. S. Lewis): What are the origins of the Green Lady in The Silver Chair?
  • The Virgin Suicides: Why did the girls kill themselves?
  • The Hitchhiker's Guide to the Galaxy: What is the Ultimate Question of Life, the Universe and Everything? Simultaneously knowing both the Ultimate Question and the Ultimate Answer would cause the universe to rearrange itself into something even more incomprehensible. This may have happened already.
  • A gag in More Information Than You Require involves Hodgman's encounter with director Peter Berg on a plane and finding out he had two copies of Dune with him on the plane, because he was planning on making a Dune movie. This does not explain why he had two copies with him. This becomes a brief running gag, in which Hodgman provides even less helpful explanations that still don't explain why he would have two copies of the book, leaving it a mystery to us all. note 
  • This is the whole point of Special Topics In Calamity Physics, which sets up dozens of mysteries and hardly answers any of them. At the very end of the book, the narrator gives a "quiz" in which she asks readers to come to their own conclusions on what happened. Ultimately, the implication is that it doesn't matter, because the narrator has moved on and grown through the experience.
  • Stanisław Lem's Solaris: Why did the planet send the replicas of people? The main theme of the novel is that we can't find out, because humans can't comprehend a truly alien intelligence.
  • Nineteen Eighty-Four raises the question of whether Emmanuel Goldstein and his revolution against the Party actually exists, or if they're simply a fabrication the Party uses as a target for the population's hatred and as bait to weed out dissidents. O'Brien states quite firmly and adamantly that Winston will never learn the truth about this. He also tells him it doesn't matter if Big Brother is an actual person or simply a representation of the Party. Seeing as how the Party changes records, it's hard to tell how much truth there is in any claim they make.
  • In Tim Powers' On Stranger Tides, a pirate decides he'd rather be shot than hanged, and asks his Navy captors' leader an Armor-Piercing Question ("Is it true what Panda Beecher once told me about you?"), that implies the captain is either a smuggler or a sexual deviant. This provokes a fight in which the enraged captain is killed. After escaping, the pirate explains his ploy to his accomplice, and admits that he hadn't actually known anything about the captain: he just knew lots of Navy officers smuggled for Beecher or patronized Beecher's whorehouse, and they'll never know which offense the dead man assumed he'd been accused of.
  • In The Shining — who is the Manager of the hotel that the ghosts refer to?
  • In Malodrax, both Lysander and Corvin wonder for some time whether the "people" who used to live on the eponymous planet are a native alien species or heavily mutated humans. It's never resolved, and Lysander isn't interested in returning to Malodrax ever again.
  • In The Tripods books, there are suggestions that the Sphere Chase is more than just a sport. Our heroes first become aware of it when they encounter two tripods practicing for it while on patrol. After Ruki is captured, he refuses to discuss the game, even though he does answer questions about the city and his race which are far more damaging.
    • An initial theory is that the tripods could be mating, however this is proved incorrect when the main characters find out the Tripods are just vehicles for aliens, not aliens themselves.
  • Why did Dracula move to the US in the 1970s? This is a minor Running Gag in Fred Saberhagen's New Dracula series. Several times someone asks Dracula why he left Europe and he starts to reply with something like, "I came here because I like your—", only to be interrupted before he can finish by an American talking about something else.
  • In the Sherlock Holmes story The Five Orange Pips, while Holmes's explanation certainly makes sense, the mystery is never conclusively solved, as the primary suspects vanish without a trace with only vague hints as to their fate.
  • In David Copperfield, Ham Peggotty swims out to sea to save a shipwrecked man from drowning. Shortly afterwards, both their bodies are washed up on the shore and the other man turns out to be Steerforth, who seduced and then cruelly abandoned Ham's fiancée Emily. It will never be known whether Ham tried to save Steerforth or drowned him.
  • In Algernon Blackwood's "The Man Who Found Out", an explorer discovers the ancient Tablets of the Gods, reputed to explain the true purpose of human life. Once translated, their revelations cause him and the friend who inherits the Tablets to succumb to despair, then go to extreme lengths to conceal their contents: contents that the reader never learns, apparently mercifully.
  • A Series of Unfortunate Events loves this. What were the exact circumstances surrounding the death of the children's parents? What was the cause of the schism in VFD? What was the exact cause of the death of Olaf's parents? (All we're told is that it involved poisonous darts and it was hinted that the children's mother was a part of it.) What happened to the people living on the island? Did they reach the horseradish factory in time, or did they die of the spore poisoning? What happened to Fiona, the hook-handed man, Hector, Duncan, Isadora, and Quigley? What is the Great Unknown? What was in the Sugar Bowl, exactly? What was the fate of the guests at the hotel? Who was the father of Kit Snicket's baby? That's not even half of them all.
    • There was also a scene on an island that everything washes up on eventually. They listed quite a few objects and vaguely hinted of the stories behind them.
    • The Great Unknown's identity has been hinted by the prequel All the Wrong Questions to be the Bombinating Beast, a Cthulhu-esque urban legend, a statue of which is the story's main MacGuffin.
    • More than a decade later, most of these mysteries were unexpectedly resolved by the live-action series, likely due to this trope being harder to do in a visual rather than literary medium. To wit, the Great Unknown is indeed the Bombinating Beast; the father of Kit's daughter is, quite logically, her boyfriend Dewey Denouement; the Sugar Bowl contains the antidote for the bad guys' fungal bioweapon (which has always been the most popular fan theory); Olaf's father was accidentally killed by Beatrice during a quarrel with Olaf, which also led to the Schism and Lemony Snicket being framed for murder; and most of the characters who ended the books on an Uncertain Doom note are given concrete fates.
  • Machado de Assis wrote a book that's been interpreted in different ways since 1899. The story is about a man that tells the story of his life, his love for Capitu (his wife) and his doubts about her adultery. No one can ever tell if the protagonist was right, and his wife cheated on him, or if madness and jealousy had simply taken their toll. Even today.
  • In The Princess Bride, William Goldman (who claims to be merely editing the original Morgenstern) notes that the original manuscript ended on a 'Lady or the Tiger'-esque note, with Humperdinck and his cronies pursuing the four fugitives, who experience a number of setbacks. He further claims that it's left permanently open-ended as to whether or not they got away and lived Happily Ever After, but that as far as he's concerned, they did. Of course, Goldman is the actual author of the book, so the ending isn't really ambiguous. For an anniversary edition of the book, Goldman included the first chapter of the "sequel" (which, according to his Literary Agent Hypothesis, he can't publish in full because the rights to the original work were given to Stephen King instead). The chapter picks up where the previous book supposedly left off and then goes in a very strange and fantastical direction.
  • The Inspector Morse short story "Morse's Greatest Mystery". The initial crime (a theft) is never resolved, or even substantially investigated.
  • Lieutenant Hornblower leaves unanswered a question that formed a key plot point in the novel: How did Captain Sawyer fall down the hatchway? Did he fall? Was he pushed? If so, by whom? This is the only Hornblower novel not to be told from the titular character's perspective, and in the story itself, Lieutenant Hornblower is quick to begin an investigation of the incident during the confusion left by the Captain's incapacitation, with the only other witness to what happened being his assistant. By the end of the book, the other man has died in a shipwreck, and Hornblower himself never reveals the answer.
  • More Than This leaves a couple of mysteries unresolved at the end of the book: What caused the fire that burnt down the area on the other side of the train tracks? Who or what is the Driver, and why did he save Seth's life, after seemingly trying to kill him?
  • Harry Potter:
    • In Harry Potter and the Order of the Phoenix, what was behind the impossible-to-open door in the Ministry of Magic, that not even the Alohomora charm could unlock? It's hinted the Ministry are researching The Power of Love in there, but why that room alone would require such powerful defenses is never revealed.
    • Were the Deathly Hallows really created by The Grim Reaper, or did the Peverell brothers actually invent them? If the brothers created them, how were they able to get them to break the laws of magic?
    • What happened to Lavender Brown? She was last seen being mauled by the cannibal werewolf Fenrir Greyback, and the film version in particular strongly implies she didn't make it, but not only has Word of God not offered a conclusive answer, it has CHANGED its answer, with Pottermore first calling her dead, then missing, before finally deleting all reference to her fate entirely.
  • Was the titular Alaska's death in Looking for Alaska an accident or a suicide?
  • In Fifty Shades of Grey, why did the press-averse Christian Grey agree to be interviewed for a college newspaper?
  • In Judy Blume's Superfudge, neither Peter nor his parents have any idea where Fudge learned how to spell "Maine", and trying to get a straight answer out of the four-year-old would have been an exercise in futility.
  • Star Wars Legends: What, exactly, happened in the thousand-year-long "dark age" before the rise of Darth Bane? This is far and away the least represented period of Galactic history in the fiction, notable only for the Star Wars: Knight Errant comic and a few standalone short stories and RPG adventures. Everything fans know about it comes from the reference books, which describe it as an anarchic time marked by feuding Sith Lords and a virtually powerless Republic.
  • The Fault in Our Stars: What happened after the end of An Imperial Affliction, the in-universe novel that stops mid-sentence? Gus and Hazel meet the book's author, but he turns out to be a total Jerkass who very bluntly tells them that it doesn't matter what happened because it's fiction and ceased to exist after it ended. This doesn't satisfy them, but they never do get an answer.
  • In Murder on the Orient Express, Poirot finds explanations for all the discrepancies and mysteries he's come across during his investigation ... except whom he'd seen wearing the scarlet kimono. He makes a good guess who owns it, but also concludes that suspect never left her compartment.
  • What was The Name of the Rose?
  • The Ascendant Kingdoms Saga: Did Meroven's war mages mean to intentionally destroy the source of all magic in the Ascendant Kingdoms with their Fantastic Nuke, or was it simply an unforeseen consequence of something they did for military reasons?
  • We Can't Rewind: How exactly did the "Freaky Friday" Flip between the parents and children occur, and will they ever find a way to reverse it? By the end of the book, they still haven't found any way to do it, and narrator Don Richards strongly implies that they've given up trying to answer these questions.
  • The Elves and the Otterskin by Elizabeth H. Boyer: Who is Eilifer, and what's his secret? Ivarr is forced to help a group of outcast elves, who are supposed to be incompetent as both warriors and mages. As they unravel the truth about the political conspiracy they're accidentally at the heart of, they gradually develop both competency and confidence. Hints are dropped throughout the story that Eilifer is lying about his competency level from the beginning, is both extremely powerful and extremely reluctant to use his power, and that he has some kind of connection to the Elf King. When he lets three witches turn him into a horse for hag-riding to protect their usual victim, the witches are horrified to discover the new horse they've created is grey because only the Elf King has grey horses. Ivarr's group - and the witches themselves - are amazed to discover that Eilifer is powerful enough to defeat three powerful witches single-handedly, but he and the witches won't talk about it. At the end of the story, Ivarr acknowledges that Eilifer remains the story's unsolved mystery, to which Eilifer simply smiles.
    Ivarr: What do you really believe, Eilifer?
    Eilifer: I believe we'd better hurry back or Finnvard will be prostrated with the fear that we're lost. Isn't it amazing how his powers of precognition are developing? Sometimes all it takes to jolt a slow learner is a crisis or an accident of some sort. And Skapti is amazing, isn't he?
    Ivarr: All right, I won't ask you any more questions.
    Eilifer: Good. What a relief. I wouldn't answer them anyway.
  • In The Westing Game, practically all the novel's mysteries are wrapped up by the end, except the identity of the person who stole Sydelle's shorthand notebook. The thief who's been purloining other items in Sunset Towers comes under suspicion initially, but it turns out that it's Madame Hoo, who'd known nothing about the Game at the time and hence, had no motive to steal a half-used notebook with no resale value.
  • In The Divine Comedy, it is principally impossible for anyone to learn why only Peter Damian was sent to meet Dante on Saturn, except God. Even the highest angel in Heaven cannot pierce the Deep Mind so deeply to fully understand His reasoning in instances of this kind.
  • Villains by Necessity: The details of Sir Pryce's Test remain unrevealed during the book. As he never speaks, this isn't surprising. Even after he does start talking, it's about something far more important.

    Live-Action TV 
  • Babylon 5: Why does every sentient species in the universe have a dish that is identical to Swedish meatballs?
    G'kar: I suspect it's one of those great universal mysteries which will either never be explained... Or which would drive you mad if you ever learned the truth.
  • Battlestar Galactica (2003): Who or what is behind the virtual beings? All we know is that it doesn't like to be called "God."
  • Beauty and the Beast (1987): Why is Vincent a beast? Who left him outside St. Vincent's hospital and why?
  • In The Big Bang Theory episode "The Closet Reconfiguration", an unopened letter to Howard from his father is read (out of typical lack of respect for privacy) by Sheldon. Howard, upset that his father had left when he was a child, burns the letter, but Sheldon is coaxed into revealing its contents to all the other characters except Howard. At the end, Howard is unsure whether he wants to know as well, and the gang devise a quantum-uncertainty-inspired solution to achieve both knowledge and ignorance: Each of them tells him one possibility for what the letter said, only one being correct (except Sheldon, who said it was a treasure map). Howard hopes they were all true. (Later events do increase the likelihood for one of them, but we, along with Howard, still don't know for certain.)
  • What was in the Christmas present from her parents that Temperance finally opens at the end of a Bones Christmas Episode?
  • In one episode of Boy Meets World the characters engage in an Escalating War and it's never explained how they pulled off certain outrageous pranks. Like, how the hell did Cory and Shawn move Rachel's car into her dorm room? And where did Rachel, Jack and Angela get that bear?
  • In Buffy the Vampire Slayer, what was Buffy's heaven? Was "Normal Again" true? How did Warren learn how to build Ted-level robots? How did Anya cause the Russian Revolution? Exactly how close were Ethan and Ripper? What is the origin of Faith's tattoo? (Explained in one of the books: it's the Mark of Kakistos, gotten while she was being possessed by a pissed-off dead Slayer.) Did the PTB extract Angel from that Hell Dimension? How did Buffy and the gang save the world and from what in "The Zeppo" (the episode focused on Xander and an unrelated event, so the audience only gets glimpses of what Buffy's doing)? The goddamned Cheese Man.
  • In the Diagnosis: Murder episode "Rear Windows '98" the culprit is caught, but he refuses to say why he did it when questioned.
  • Doctor Who:
    • The Doctor's backstory was clearly intended as this during the show's early years. His backstory is fairly well-codified now (save for some prominent gaps that simply cannot be answered without derailing the show), but the show ran for over a decade before the Doctor's home planet was even named, let alone running arcs about him becoming Lord President of Gallifrey. There are two that will probably remain perpetually unknown, though:
    • Similarly, in Who spin-off Torchwood, Captain Jack Harkness reveals that he took his name from some poor soldier who died in WWII. So... what was he named before that? We don't know. Even his brother calls him "Jack". This one was eventually answered, though — his birth name is Javic. Javic Thane.
    • Played for Laughs in Comic Relief parody "The Curse of Fatal Death" — his companion frequently asks "why/how/what [whatever]?" and he always answers "I'll explain later," but the explanations never happen. This is a reference to the many, many times he said "I'll explain later" or something similar on the show. Specifically, why the Daleks chose to not exterminate the Doctor and Emma, why there are chairs on a Dalek ship, and exactly why the Master is called "The Master". He is called "The Master" because he chose to call himself "The Master", for pretty self-explanatory reasons. Also, it's a play on the fact that both "Doctor" and "Master" are academic degrees.
    • In "The Empty Child"/"The Doctor Dances", Captain Jack says he left the Time Agency because they stole two years of his memories. This has never been clearly explained, although some EU sources have taken stabs at it, and on Torchwood, memory-manipulator Adam once held the memories hostage. Some fan theories have it that the memories were erased because of Jack discovering that he would eventually become immortal.
    • Pretty much everything about the monster in "Midnight". What was it? What did it want? Did it know the Doctor? How was it able to survive on a planet flooded with deadly radiation? Was it intentionally malicious, or just strange? How much of the events of the episode was the creature's doing, and how much was the passengers' paranoia? Is it dead? Not even the Doctor knows the answers.
    • Throughout "The End of Time", a mysterious woman continuously appears to Wilfred Mott, steering him towards meeting the Doctor. At the very end, she appears alongside the Big Bad, and her presence is enough to convince the Doctor not to attack him, and apparently getting Killed Off for Real. Once everything is over, Wilfred asks the Doctor exactly who she was. He never gives an answer, and immediately changes the subject.
    • "Deep Breath": Did the Twelfth Doctor shove the Big Bad off the hot air balloon, or did the Big Bad jump? (Inquiring Missys want to know!) The baddie had to die to stop the threat posed by him and the other cyborgs, but as is discussed in-story, option one requires the Doctor to violate his Technical Pacifist principles against killing in cold blood, and option two requires the cyborg to violate I Cannot Self-Terminate. So one of the two was lying about their "programming" — but which one?
    • "Flatline": Were the Boneless malicious or Obliviously Evil?
    • "Listen": So, did the "perfect hider" ever exist at all? There's a perfectly logical explanation presented for everything in the episode, but some of them are more contrived than simply assuming the hider exists.
    • There's also the twofold question of the original Osgood and her Zygon duplicate. First of all, which Osgood did Missy kill, and which one survived? And second of all, which of the current Osgoods is from the original pair, and which is the Zygon replacement for the deceased Osgood? Only the Osgoods themselves know — and in the name of peace between humans and Zygons, they're not telling.
    • In "The Pilot", Bill's Love Interest Heather is turned into the titular entity by a puddle of leaked fluid left behind by a spaceship. Throughout the rest of Bill's tenure as a companion, even after Heather's return in "The Doctor Falls", it is never explained where the fluid came from. Since Heather effectively became a Physical God as a result, this is especially intriguing. The circumstances of Bill's final appearance, "Twice Upon a Time", suggest that this mystery may never be solved.
    • "The Ghost Monument": The planet Desolation was knocked out of its usual orbit sometime before the beginning of the episode. Since the Doctor's teleporter, and Angstrom and Epzo's spaceships, all send everyone to Desolation's former position (leaving the Doctor and company briefly exposed to the vacuum of space), it can be concluded it happened recently. But how? One possibility is that the party responsible for the planet's, well, desolation, the Stenza, could have done it, but it's implied they haven't been back there for centuries. Was it a natural event? Was it Ilin, the person running the race Angstrom and Epzo are participating in? Or was it something else entirely?
    • "It Takes You Away": Ribbons, the mysterious alien the Doctor, Graham and Yaz meet in the antizone. Who and what is he? Where did he come from? And how did he end up in the antizone? He dies before any of those questions can be answered.
  • ER:
    • Who beat Dr. Greene to a pulp at the end of season 3? The assault causes Greene to temporarily go off the deep end and start stalking Chris Law, the disgruntled brother of a man who died under Greene's care, but Law is ruled out as the culprit and in fact Greene ultimately apologizes to him.
    • Did Dr. Gant fall onto the train tracks, or did he jump?
  • Farscape: Who killed Salis in "Durka Returns"? Chiana, Durka or somebody else? (There's a widespread Epileptic Trees theory that it was Zhaan.)
  • Firefly: Due to the series's early cancellation, we never got any definite answers about the Blue Sun Corporation, especially what it was up to under the radar of the Core Worlds. Judging by River's reaction to their corporate logo, nothing good.
  • The kangaroo from Flash Forward. Even if the series hadn't been cancelled, chances are good that they never would have explained it.
  • Game of Thrones:
    • No one knows the circumstances of Lyanna's abduction by Rhaegar Targaryen, we only know how it ended: her Death by Childbirth giving birth to Jon Snow and Ned promising he would protect the boy.
    • Tyrion has spent several years wondering why Orson was obsessed with smashing beetles in the garden. Fans of the show seem to believe Orson represents either the author George R. R. Martin himself (he senselessly kills his characters while the fans wonder why), or the random cruelty of the Gods, or the meaningless nature of the universe.
    • What happened when Tyrion brought a donkey and a honeycomb to a brothel?
  • Get Smart: What is Agent 99's real name? In the episodes featuring 99's mother for instance, said mother uses euphemisms such as "darling" or "dear", further hiding the answer.
  • In Glee, how did Finn Hudson die?
  • Horatio Hornblower: What happened in "Mutiny" when Captain Sawyer fell down the hatchway? Was it an accident? Or was he pushed? If he was pushed, who pushed him?
  • House:
    • When Kutner killed himself, there was no buildup leading to his suicide, and in the aftermath no one was able to find any reason why he might have done it. Since House's main source of fun in life is finding answers to mysteries, he finds this extremely frustrating.
    • No explanation was ever given, nor intended, for why House was shot in the second-season finale. Nor for what became of "Harpo" in the same episode.
  • How I Met Your Mother:
    • In the episode "Zoo Or False", we don't find out how Marshall's wallet went missing. Nor do we find out whether Bobo really escaped from his cage, stole a doll and climbed Ted's model of the Empire State Building while the cameraman threw paper airplanes at him.
    • In "The Pineapple Incident", which gives us the page image, Ted wakes up with a pineapple on his nightstand with no memory how it got there. However, a deleted scene from an episode made eight years later did reveal what happened, because the writers did actually want to resolve that plot point.
  • The main characters in Leverage all eventually find out, but we the audience are never told what Sophie's real name is.
  • Many plot points of Lost are considered this, but for a specific example, the identity of the shooters in the second outrigger ("The Little Prince", Season 5) became sort of a running joke among the producers: due to Time Travel being involved, too many possible candidates for the role exist and not once has an attempt been made to narrow the circle down.
  • Parodied in the Mystery Science Theater 3000 episode Prince of Space: Japanese reporters are awaiting the scheduled arrival of a space invasion:
    Reporter #1: One minute to 8:00.
    Reporter #2: Is your watch right?
    [A noise is heard and everyone suddenly goes to investigate]
    Mike: (Somberly) Is his watch right? We may never know.
  • NCIS: How does Gibbs get those boats out of his basement?
  • Spoofed in NewsRadio when there's an election for news director. Everyone tells Dave they're going to vote for him, but he ends up not getting a single vote. Afterward, Bill assures Dave that he supports him completely. When Dave asks why Bill didn't vote for him, he replies "I still think I did. I guess it's one of those mysteries we'll never know the answer to."
  • In One Foot in the Grave:
  • Seinfeld:
    • Seinfeld is the Trope Namer with the episode "The Pie". The very first scene of the episode has Jerry offering his Girl of the Week a slice of apple pie, which she refuses to taste. She doesn't give a reason, just shakes her head, and Jerry becomes obsessed with figuring out why she won't try the pie. He rules out a lot of possibilities, but by episode's end, he's still as clueless as ever.
      George: Did you ever solve the riddle of the pie?
      Jerry: No, that's one for the ages.
    • In "The Seven", Jerry dates a woman who always appears to be wearing the same dress. He wonders if she never changes her clothes, if she has a closet full of dresses like that, or if it's something else entirely. He never finds out and neither does the audience.
  • Six Feet Under: It is left somewhat unclear whether Lisa's death was an accident or a murder, as well the paternity of her and Nate's daughter Maya.
  • From Stargate SG-1, who were the aliens whose ship attacked the Prometheus in "Grace"? Who and what the Furlings were is also never stated.
  • Star Trek: The Next Generation:
    • In "The Next Phase", when Geordi and Ro were presumed dead, Riker planned to say something about Ro. Since they returned at their memorial service, we never hear it. What did he intend to say?
    • Whatever happened to the signal sent to a remote area of the galaxy by the parasitic aliens at the end of "Conspiracy"? We'll likely never knownote .
    • In the end of "Hollow Pursuits", Reg Barclay deletes all his holodeck programs except for "Program 9". What was in that program, and why was it worth saving? Going by a conversation between Worf and O'Brien on Star Trek: Deep Space Nine, it's possibly the "Three Musketeers" program.
  • That '70s Show: Where exactly is Fez from? In the second-to-last episode, it turns out that Fez and his friend themselves don't know the name of their homeland, as the British are too stuck up to tell them and the Dutch they can't understand.
  • That Mitchell and Webb Look:
    • What does the word "Numberwang" mean, and what are the rules for determining whether something is Numberwang? Bertrand Russell apparently realized the answer while staring at a jug on his desk, but he destroyed the jug so nobody could copy his work. There's a living computer named Colosson which knows the answer, but its extreme views on what to do to non-Numberwang objects make it a bad idea to ask it. Everyone else can only find out by carefully checking all 37 volumes of the rules, which are written in a code which is never explained.
    • What was The Event in the "Remain Indoors" skit? Why do the characters all keep getting traumatic memories of it?
  • On Top Gear, the real identity of The Stig. Or the age of The Stig. Or the origin of The Stig. Or anything about Stig beyond "tame racing driver." There was some suggestion that the Stig is in fact Michael Schumacher, but after he got lost on the test track it seemed disproved. And when The Stig actually revealed his identity in an interview (not on the show), he was promptly fired for breach of contract and a new Stig was found (in Jerusalem, by the three wise(cracking) men, aka the hosts. It was...weird).
  • In Twin Peaks, the question "Who killed Laura Palmer?" was intended to never be answered, but was forced to be resolved due to Executive Meddling.
  • Much like the comic, The Walking Dead has never definitively answered what caused the virus that reanimates the dead. There have been hints dropped here and there (the first-season finale suggests that the virus attacks the brain, then restarts the brain stem after the victim dies; the first season of Fear the Walking Dead suggests that there was a flu-like virus that may or may not be related), but never anything concrete.

  • In the comedy song "The Homecoming Queen's Got A Gun", we'll never know who Johnny was, because only Debbie knew and, like, she's dead.
  • The opening chord of The Beatles' "A Hard Day's Night." It was determined to be a simultaneous combination of guitar and bass chords played by Harrison, Lennon and McCartney, as well as a piano chord by producer George Martin. Debate continues over the exact notes contained within the chord.
  • Carly Simon's famous "You're So Vain." Exactly who the song is about is still unknown, though Dick Ebersol, president of NBC Sports, won the right to know the secret at an auction. Various, largely conflicting clues have been released over the years. In November of 2015 she revealed the second verse is about Warren Beatty, but we still don't know who the other two verses are about.
  • The identity of rapper Captain Murphy. Theories range from another persona of Tyler the Creator to obscure cult act Zeroh to singer Thundercat to experimental beatsmith Flying Lotus. The answer eventually turned out in real life to be FlyLo. In-universe it's still an open question.
  • For much of the 1970s, there was speculation about blues/jazz singer Leon Redbone's true identity. He always performed in dark glasses and never took off his panama hat. He also had a big Groucho mustache. The most common story was that he was an alter-ego of Frank Zappa. Others held that he was another Andy Kaufman character. Given that he is still performing and both Zappa and Kaufman are dead...or are they? Eventually it turned out he was simply Leon Redbone, birth name Dickran Gobalian.
  • The identities of Doctor Steel and Rucka Rucka Ali are similarly mysterious.
  • Ylvis's song "The Fox (What Does The Fox Say?)" poses but never answers the question, "What does the fox say?" This is a reference to how other animals have well-known onomatopoeic sounds ("Dog goes woof, cat goes meow, bird goes tweet, and mouse goes squeak...") but foxes don't. In Real Life, foxes make a variety of sounds, and words do exist for certain fox sounds, including "gekker" (for chattering) and "yiff" (for barks that foxes allegedly make while mating). Of course, the term "yiff" has a bad connotation after the Furry Fandom adopted it to mean furry porn.
  • The 5 Seconds Of Summer song "End Up Here" centers around the protagonist (and his friends) wondering why a particular girl is interested in him. He's too insecure to ask her, though, and never does find out.
  • Just what is the thing in the box that everyone finds so offensive in the '50s novelty song "The Thing"?
  • Why exactly did Major Tom's communication cut out at the end of "Space Oddity" by David Bowie?
  • Michael Jackson's "Billie Jean" never outright states whether the eponymous woman's son was fathered by the narrator or not, and by extension whether the narrator is a deadbeat dad trying to dodge responsibility or an innocent man being harassed by a crazy woman trying to extort him.
  • In Nine Inch Nails' "Hurt," just who is the narrator's "sweetest friend" whom the song is addressed to? Given that the narrator is a depressed heroin addict, one theory is that it's not even a person and he's talking to his drugs.
  • Paul Simon's "Me and Julio Down by the Schoolyard" has the Noodle Incident that Mama saw. Simon gave this one a Shrug of God in a later interview: "I have no idea what it is. [...] Something sexual is what I imagine, but when I say 'something', I never bothered to figure out what it was. Didn't make any difference to me."

    Myths & Religion 
  • The Bible:
    • Where was Jesus and what was he doing between the ages of twelve and thirty-ish? The Gospel writers were not the least bit interested in even hinting at it (save for a glib, hasty note about him "growing in wisdom and spirit", which tells us nothing specific).
    • The pronunciation of the God of Israel's true name, YHWHnote , is unknown, as the Hebrew alphabet of the time did not include vowels. The most commonly used pronunciations are Yahweh and Jehovah (the latter of which Hebrew linguists universally agree was not the original pronunciation). Jewish tradition forbids uttering the name of God, and the word Adonai is used instead. In English translations of the Christian Bible, YHWH is mostly replaced with lord, one of several translations for Adonai.
    • In John's gospel, what does Jesus write on the ground when he stops the stoning of the adulterous woman? The sins of the woman's accusers is a popular theory.
    • In 2 Corinthians 12:7, the Apostle Paul mentions that he was given "a thorn in the flesh." While this is generally agreed by scholars to refer to some sort of ongoing difficulty in his life, the jury is out on what specific thing it actually is. Theories range from physical disabilities like poor eyesight or epilepsy to circumstantial factors like constantly dealing with persecution to spiritual difficulties such as struggling with a particular sin. Whatever it is, he never explicitly describes it.
    • So who was Darius the Mede, anyway? He's mentioned in the Book of Daniel as a ruler of Babylon between Belshazzar and Cyrus the Great - only problem is, he doesn't appear in any other record of Babylonian rulers. Guesses for his identity range from Cyrus' son-in-law Darius I, projected two generations backward by the author of Daniel (the book was written much later than when it was set) whether accidentally or deliberately, to Cyrus's governor of the city to a completely mythical figure.
    • What exactly were the Nephilim? They're mentioned exactly twice, once in Genesis and again in Exodus, in a way that suggests the author(s) assumed the reader would already be familiar with them. All that's known is they lived just before the Great Flood, and were very strong. Apocryphal books describe them as angel-human hybrids, though this is not considered Canonical.
    • Where did Cain gets his wife? Biblical scholars have argued about this for a long time, whether she was another child of Adam and Eve, or possibly made by God like Adam and Eve.
  • Norse Mythology:
    • What did Odin whisper to his late son Baldr's (the first Aesir ever to be Killed Off for Real) ear at his funeral?
    • Odin's two brothers, Vile/Honer and Ve, who helped him create the world and the creatures in it, simply disappear one day. Odin goes to great lengths to find the answer to their disappearance, finally sacrificing his one eye in the Well of Wisdom (as the eye can then see the past, present and future). Yet, he never tells a living soul the answer except his wife. He reasons that "What three know, the whole world knows."
    • When Baldr has been slain Odin rides to the death realm, overcoming many perils for twelve days in order to find him. Finally he meets an old witch. Having spoken with her Odin abandons his search and goes back to spend his days preparing for Ragnarok. He never reveals to anyone what the witch said.
  • Exactly what is The Sampo? (In the The Kalevala, it was interpreted as a mill that produced unlimited quantities of salt, flour, and gold, but this is just an addition of the 19th century compiler; the original tales do not actually say what Sampo is.)
  • In Egyptian Mythology, just what was the real-life inspiration for Set's animal form, if there indeed was one at all?

    Tabletop Games 
  • What are the Dark Powers of Ravenloft, and what are they up to? Word of God from TSR's writers and canon statements from Arthaus proclaim that this will never be revealed, and a novel that dared to try it was declared non-canon for doing so. Also, what actually happened when Strahd and Azalin found themselves in Mordentshire during their botched attempt to break out of the Land of Mists?
  • What is the Lady of Pain of Planescape?
  • Warhammer 40,000 is chock full of these. Some of the biggest are:
    • What happened to the missing Primarchs? Is the Emperor truly alive or dead? What was the Pale Wasting?
    • Practically everything about the Alpha Legion. Is Alpharius really dead, and if so, who killed him? Was it Roboute Guilliman? Was it Rogal Dorn? Is Omegon still alive? Did Alpharius even die at all? Maybe "Alpharius" confessed he was a Fake Defector for the Imperium during the fight and Guilliman agreed to fake his death, or maybe Alpharius actually killed Guilliman and adopted his identity. The clash may not have even happened at all. Also, are they loyal to Chaos, to the Imperium, to nobody, or to some mysterious third organisation that also seeks the destruction of Chaos?
    • Are Cypher and the Fallen Angels loyal to Chaos or not?
    • Most, if not all, of the mysteries are left deliberately unanswered, as it allows players the maximum scope in interpreting the lore to customize your armies in whatever way the player feels is most interesting to them.
  • Eberron has a number of these, added intentionally so that DMs have leeway to make stuff up while still sticking to the setting. Examples include: what actually triggered the Mourning, do the Sovereigns and Dark Six actually exist, and what are the long-term plans of enigmatic factions like the Lords of Dust, Inspired, and Chamber.
  • The GURPS setting GURPS IOU runs on this. IOU is Illuminati University... so what does the "O" stand for? Just who (or, for that matter, what) is the ArchDean anyway? Who is the Unseen Dean, and how many have they gone through? And what's the janitor's deal, anyhow? The answer to all these, and more, is frequently "You're not cleared for that." It even says so on the back cover.

  • In Gilbert and Sullivan's The Yeomen of the Guard, the jester Jack Point asks the riddle "Can you tell me, sir, why a cook's brain-pan is like an overwound clock?" He never gets the chance to give the answer.
  • In Waiting for Godot, who or what is Godot? Why are they waiting for him? Will he ever come? And just what on Earth was Lucky going on about?
  • Is it really the ghost of Hamlet's father, or just an evil spirit taking advantage of Claudius' crime to cause the prince even more misery? Or is Hamlet just crazy?
  • The "Dark Lady" who inspired many of Shakespeare's Sonnets may never truly be identified, although there have been many suspects named by scholars.
  • Did Father Flynn of Doubt really molest an altar boy? Only the playwright, and the actors that played him on Broadway and in the movie know for sure.

    Video Games 
  • The Legend of Zelda:
    • Are the Gorons a One-Gender Race or is it we just never see the females? Are the asexual? How do they reproduce?
    • The Legend of Zelda: Ocarina of Time: Did Zelda actually change gender when she became Sheik, or did she just change her appearance? The general consensus (backed by the English versions of Super Smash Bros. Melee and Brawl) is that Zelda's magic superficially affected parts of her appearance (clothes, eye color, and skin color), but fan debate continues to this day.
    • From The Legend of Zelda: Breath of the Wild, how Ganon became Calamity Ganon. It is implied to be the result of either one of his incarnations failing to reincarnate or Demise's curse completely overtaking him until he became little more than a being of pure hatred.
    • Also from Breath of the Wild, why do the Gerudo let the all male Gorons in when they exclude men? Not even the Gorons know this one.
  • In the Super Mario Bros. games, just who is Bowser Jr.'s mother? Why did Bowser lie to him about it? Why does he keep kidnapping her if he knows she isn't his mother? Why didn't Princess Peach protest when he said that she was his mother? The closest thing to a resolution is Shigeru Miyamoto joking that he is Bowser Jr.'s mother.
  • Touhou has a crapload of this, probably as ZUN's way of encouraging fanwork. What happens if Rumia's ribbon is removed? What's the deal with Flandre's wings? What's Sakuya's backstory, and why was Eirin surprised to see her? Just how powerful would Alice be if she went all-out? What happened to Youki? Just how old is Eirin, anyway? What's Maribel's deal? Where exactly is Gensoukyounote ? How much of the PC-98 games are canon?
  • What is the name of the protagonist in Gothic? What was he imprisoned for?
  • Who exactly was the Head from the first Myth series game, and what happened to it?
  • Pokémon:
    • Just what the hell does the rest of Diglett and Dugtrio's bodies look like? And what do Cubone and Marowak's heads look like under the skull they wear?
    • What does the inside of a Pokeball look like to a captured Pokemon?
    • Where do Pokémon eggs come from? Despite the fact that you can leave Pokémon in Day Cares and they produce eggs, nobody (not even the daycare staff) have seen Pokémon mate or lay eggs. They appear to simply poof into existence. This "mystery" might have been included to keep the games child-friendly.
      • Well, they can be stored in computers...but how does that work? Digimon, for all its ripoff claims, is at least less mindscrewy about it all.
    • Meloetta once had red shoes, but it lost them at some point. What these shoes were, where they ended up, what (if anything) they did for Meloetta and how it wore them despite not having feet has never been explained.
    • The ancient Bug-type Pokémon from which Genesect was created has never been seen nor named.
    • What exactly turns a regular Carbink into a mythical Diancie? It's apparently a sudden mutation which is a separate phenomenon from regular old evolution and the trigger is unknown. There's also no way to trigger this mutation in the games, either.
    • How are Aerodactyl and Mewtwo able to Mega Evolve, despite coming long before and long after (respectively) the advent of Mega Evolution itself?
    • How did Alolan Raichu evolve into their Electric/Psychic form? No-one knows; as far as the populace is concerned, maybe they ate too many pancakes.
    • Where has Team Rocket's leader Giovanni gone? This eventually leads to a veteran trainer/ex-member (found at the end of Malie Garden's Nugget Bridge challenge) musing over his disappearance, 20 years after the fact.
  • The Mega Man franchise:
    • Are Serges and/or Isoc from the Mega Man X series actually Dr. Wily preserving himself in robotic forms, or are they something else entirely? Inafune refuses to give the answer, saying that it's more fun for the fans to decide for themselves. However, as he is no longer involved with Capcom or the Mega Man franchise, this question could very well be answered by other creatives in the future.
    • In Mega Man ZX Advent, is Biometal Model A connected to Axl in any way, or was Master Albert telling the full truth after all?
  • In Planescape: Torment:
    • What did The Nameless One do that even a thousand lifetimes of good deeds wouldn't have been enough to atone for? For that matter, what is his name?
    • And what is it that can change the nature of a man?! Whatever you believe can change the nature of a man, can.
  • Team Fortress 2:
  • Basically everything in Yume Nikki, since there is no real plot and almost everything is a dream. There are, however, two major ones:
    • What happened to Madotsuki in the past that caused her to become a shut-in, have horrific nightmares repeatedly, and ultimately commit suicide?
    • The exact nature of the ending has been hotly debated ever since the game became available. Does Madotsuki actually commit suicide? Was the waking world of Madotsuki's bedroom actually just another level of the dream world and was jumping off the balcony the only way she could truly wake up? Did Madotsuki only think this was true and sleepwalk off the balcony in an attempt to wake up?
  • Escape Velocity Nova: A fan-made sequel replaced one of the governments from Nova with a giant hyperspace rift full of Swirly Energy Thingies and sensor interference. No explanation is ever given, though there's quite a few Epileptic Trees In-Universe. Out-of-universe, the Polaris were removed to stop their super-advanced ships from wrecking game balance.
  • Games by Mateusz Skutnik tend to have these:
    • There are almost too many to count in Submachine. But probably the biggest are, what the hell is the submachine, and who is the player?
    • If it weren't for subtle hints of meaning throughout Daymare Town, it would just be a Mind Screw. Some questions are raised in-story (is it fog or mist surrounding the town?), others remain unspoken (how did the player get there?).
  • In Persona 4:
    • A teenage girl strongly resents the department store she works at (for various social and cultural reasons). Her hatred of it is so great that it poisons her inner landscape and creates her Shadow, inadvertently causing her death...but she doesn't simply quit working there. It's never explained why. At one point, she has a flashback to her father asking why she keeps that job- he suggests that maybe she wants the money from it, or that there's someone there she wants to spend time with- but her narration doesn't indicate whether any of these guesses are true.
    • Yosuke's Social Link includes two of the girl's former co-workers, who give credit to the idea that she was working at the department store, to save up money and elope with a potential boyfriend. But the girls are unreliable sources, raising more questions.
  • The Elder Scrolls:
    • What happened to the Dwemer? They were a highly technologically advanced race who created all manner of Magitek and Steam Punk technology, which remains unmatched by any other race in Tamriel. They were also extreme Naytheists for whom a major part of their outlook was the idea of refuting everything as real. During the mid-1st Era, they discovered the Heart of Lorkhan (the "divine center" of the dead creator god of the mortal plane) deep beneath Red Mountain. Though there are many different versions of the story regarding what happened next, the Dwemer did something with the Heart that caused their entire race to disappear from every known plane of existence in a single instant. The leading theory (which you can put together yourself in the Mages Guild quest line in Morrowind) states that they were trying to break themselves down into their base elements before ascending into divine form. However, they got something wrong with the "reforging" step and instead blinked out of existence. Other theories state that they may have even been successful in their attempt, and are currently on said "higher plane." Making it only more confusing is one particular Dwemer ruin that shows whatever happened was violent and abrupt: it's a residential area, and you find piles of ash that used to be Dwemer in beds or near their piles of equipment on guard duty. Despite the theories, no definitive answer has been given in the series to date.
    • Skyrim:
      • Every other one of The Companions gives an answer when asked why they joined, but Vignar Grey-Mane only says that he's reached an age where you can't remember why anything happened, just that it did. And we never find out any more.
      • In-Universe, the mystery of the Dwemer has only deepened by the time of Skyrim since much of what was known about the Dwemer was again lost in the 200 years following the Oblivion Crisis and the eruption of Red Mountain (which wiped away a great number of Dwemeri ruins in Vvardenfell, the epicenter of Dwemer culture prior to their disappearance). Even one of the greatest experts on the Dwemer, Calcelmo, knows less about the Dwemer than some amateur archeologists in Vvardenfell during the time of Morrowind.
  • Shin Megami Tensei: What caused the endless cycle of conflict between Law and Chaos? Many different characters throughout the series offer up explanations, but they all contradict each other and it's never made clear who's right, who's mistaken, and who's outright lying.
  • What caused Ratchet to crash his ship on Novalis in Ratchet & Clank (2002)? Good question.
  • In Device 6, at the end the text reads that Anna sailed away from the island, but the pictures show her being shot and killed. Since Device 6 can alter text and images, but not both at the same time, which event really happened?
  • Katawa Shoujo: What is Misha's disability? Given her personality, bipolar disorder is a common fan guess, but Word of God has said nothing on the subject except a joking suggestion that it's a broken nail.
  • Kingdom Hearts II: What are the human names of Demyx, Luxord, and Larxene? The other organization members all appear in human form in the prequel, but these four never show up; and seeing as they also apparently are no longer considered important by Xehanort in future games, it's unlikely we'll ever learn the answer.
  • In the Danganronpa series, it's never explained anywhere why the twin sisters Junko Enoshima and Mukuro Ikusaba have different surnames. When asked about it at the end of the first game, the former says the answer is boring and that the students should figure it out themselves.
  • Five Nights at Freddy's has a few:
    • What exactly is inside the locked box at the end of Night 7 of Five Nights at Freddy's 4? While most of the apparently cryptic lore of the series tends to be explained (sort of) in future games, this particular example is likely to remain a mystery, due to Scott explicitly stating that he changed his mind on the subject of revealing it during the Halloween update.
    • Which animatronic was responsible for the Bite of '87? The first two games gave contradictory answers to the question; and while the end of the second game heavily implies a possible victim of the bite, the identity of the biter remains unknown. The fourth game ends with what appears to be the Bite in question, but according to Word of God the incident shown is actually the Bite of '83, not '87, leaving the fandom back at square one.
  • Watch_Dogs 2: What's a Frewer?
    Ray: Many scientists have worked hard to figure that out with no conclusive results.
  • Silent Hill: Is the being worshipped by the Order truly a Goddess, or is it "merely" a very powerful member of the town's monster population?
  • Nexus Clash: What really happened to all the millions of people who inhabited the human cities that got pulled into the Nexus to become Valhalla?
  • Remember11: The whole ending was one big Mindscrew especially with the nature of Keiko: was she relapsing into her murderous state or was she just being creepy?
  • Fire Emblem Awakening: Chapter 22 pits the Shepherds against the Grimleal's last line of defense keeping the heroes from getting to the Dragon's Table: Aversa and... the Deadlords, five of whom are wielding holy weapons of the Twelve Crusaders. How and where the Grimleal managed to get their hands on the Loptyrian Cult's undead generals and five of the legendary weapons of Jugdral is left a mystery.
  • Fallout: Who shot the first nuke on October 23, 2077, triggering the Great War and making the world of Fallout what is today? We don't know. Ultimately, we're unlikely to ever get a clear answer and it doesn't really matter. Whoever shot first, the world ended all the same, and the survivors were left to pick up the pieces and start again. Both the Interplay and Bethesda games offer some possible explanations, but they're vague at best. These include:
    • After having lost the Sino-American War earlier that year, China had nothing left to lose and shot first.
    • America, thinking China was too weak to do anything, tried to finally finish off their adversary and shot first.
    • Vault-Tec, wanting to either conduct their Vault experiments or just to fulfill their own prophecy of Armageddon, launched the first nukes.
    • The Zetans, who had been watching Earth for centuries and kidnapping people for experiments, tried to force the nuclear launch codes out of the mind of a top-ranking military officer and used them to trigger the war.
    • An artificial intelligence, out of boredom and wanting stimulation, triggered the war simply to witness its outcome.
    • Fallout 4: Is Kasumi Nakano a human or a synth? The Institute and Railroad both claim to have no records of her (and the former has no reason to replace her with a synth anyways), she doesn’t drop a synth component if she dies (the majority of synths you kill do), and she could easily just be dealing with mental illness and self image issues... but on the other hand, she keeps having a recurring dream about a place that sounds very similar to the Institute, her family is almost suspiciously protective of her and insistent on her humanity, Dima strongly believes that she is a synth (he’s certainly an expert on that subject), and the Institute and Railroad also acknowledge that their records aren’t perfect and there’s a real possibility she could be one of their synths after a memory wipe. The game never answers for certain and instead leaves it up to you to decide, and your character can declare that it ultimately doesn’t really matter.

    Web Animation 
  • Homestar Runner: How do you type with boxing gloves on?
    • Similarly, any information about the parents of any of the main characters save for Pom Pom and Homsar. Except Homsar claims to be the son of a cup of coffee and a chipwich, which may or may not be true.
    • As well as what Strong Bad's face looks like without the mask. He does take off his mask once while obscured by a huge chair, then states that he will never do that again. The Brothers Chaps have stated they will likely never answer these questions.
    • In the Strong Bad Email "4 branches", how did Homestar end up stuck inside the water cooler? The only explanation he gives was that he was in Barbados, hanging a picture on the wall, before Strong Bad cuts him off saying "Okay, that tells me everything I need to know".
    • In "Best Caper Ever", how did Homestar end up on an ice floe in the middle of the Arctic ocean after The Cheat peed in his melonade?
    • Why was Coach Z buying all the "great for baby" items in "garage sale"?
    • How does Homestar (and the other armless characters) pick stuff up? Do they have invisible arms, or are they using telekinesis? In "In Search of the Yello Dello", Marzipan slaps Homestar, leaving a visible hand-print, and in the commentary Strong Bad mentions what nice hands she has, suggesting she at least has invisible arms (or at least hands), but that was an early toon and it still doesn't solve the mystery for the other armless characters.
      • On at least one occasion, Homestar was shown wearing a trench coat, and the arms of said coat moved when he picked up a glass. He is also capable of flipping the bird (though so can Strong Bad and Pom Pom - see first bullet point). The implication seems to be that "armless" characters simply have invisible arms.
  • Happy Tree Friends:
    • How do the Tree Friends keep coming back to life? The real answer obviously being Rule of Funny, but since it's left unexplained in-universe it still qualifies. "Blast From the Past" and "Better Off Bread" imply that the answer is Time Travel, but at least Cuddles has been shown to remember his previous deaths.
    • How does Cro-Marmot move, and how does Handy do things that require hands when offscreen? Again, the real answer obviously being Rule of Funny.
    • Who is Cub's mother, and did she die permanently?
    • How was Flaky killed in "Happy Trails Pt. 2: Jumping The Shark"?
    • How did Handy lose his hands, and why can't he regenerate them between episodes the way Tree Friends usually do after losing body parts? Similarly, how did Russell lose his arm and eye?
    • How did Flippy get PTSD? Word of God is that this is intentionally ambiguous.
    • Is Mr. Pickels real? Is he a product of Lammy's imagination? Or something else?

    Web Comics 
  • Bob and George - How did Metool-D2 end up in the Alternate Universe? The characters know, but the audience never will!
  • How do Casey and Andy keep coming back to life? It's even been asked in-universe when Andy died and came back to life mid-strip, though he seemed unaware it happened at all, suggesting the duo doesn't know. The leading fan theory is that Satan began resurrecting them after she and Andy began dating, but they were coming back before that. With no official word on why it keeps happening, the real reason is most likely Rule of Funny.
  • Homestuck devotes most of Arc 5 to introducing the trolls- an alien race from Alternia- and explaining how their Sburb session overlaps with that of the protagonists. However, the story makes it clear that the trolls are only deuteragonists at best, and many parts of their session are excised or heavily abridged, showing only the parts of it that are integral to Homestuck's Myth Arc. Therefore, fans are free to speculate on exactly what Alternian culture is like, and the trolls' lives before the game.
    • A specific example: What was that 'little moment' between Terezi and Karkat when she got close enough to learn his blood colour?
    • Where did Sburb really originate? Why does it even exist?
    • In-Universe example: The Ultimate Riddle.
  • Nothing about minus is ever explained, most importantly: where do minus's powers come from in the first place? What, exactly, are her parents? Epileptic Trees on this one range from beings even more powerful than minus herself to completely ordinary humans who just happen to have a Reality Warper for a daughter, if they are even her biological parents at all. Of course, since all the readers ever "see" of them is minus's mother yelling from off-panel, no one will ever know. This and the previous question go answered because they aren't necessary to enjoy the comic and there is a risk of any explanation ruining the mystique, but a much more light-hearted unanswered question is: other than minus and a few minor characters, what are everybody's real names?. And why is minus' name always written in all lowercase letters?
    • An example unrelated to the title character is the case of the sinister man claiming to be a chalk salesman from issue 106. He appears to be more powerful than minus, and his stuffing her into his briefcase initiates the chain of events that ultimately results in her causing the apocalypse a few issues later, but whether he intended this to happen, and precisely who or what he is, are never revealed, and he never appears again.
  • Shortpacked! contains a couple, the most glaring one being Galasso's resurrections of Ronald Reagan and Jesus. Resurrection tech exists in the comic's universe, but it explicitly requires nine months to work (Mike showed up after being dead for five) and the subject's DNA (all of Mike's was destroyed), and it's also under government lock and key with an extensive waiting list. There's also the matter of the Drama Tag, the pulling of which may or may not have resulted in a Cosmic Retcon of Amber's childhood if it even exists at all.
  • Sluggy Freelance - "Who murdered Sherrif Deer?"

    Web Original 
  • Marble Hornets never explains what "the ark" that totheark was looking for was or why it was so important. It doesn't help that totheark is the only one to ever talk about whatever it is and even when he begins appearing on screen pretty regularly toward the end, he'd essentially stopped talking about it and seemed to be working on completely unrelated matters.
    • Another, more production-wise riddle is "How was the Operator character physically made?" None of the producers will tell us because apparently the answer is so mundane and obvious that revealing it would ruin the fear it brings to the series. All that's confirmed is that it's not a mannequin.
  • The SCP Foundation is made of this trope. Where do SCPs come from, and how the hell do they work? What does 447 do with dead bodies? What are 055 and 579? Nobody in-universe can remember anything about the former except what it isn't, and the latter's file is entirely expunged. What, if anything, can kill 682? What is Procedure 110-Montauk, and what entity is it protecting the world from? Which of the 001 proposals is real? Is 343 God, or is he just a reality warper with a god complex? How did the Foundation originate? Is Clef Satan? Among many, many others.
  • There's some random kid playing a video game in the Time... Lab during the Christmas episode of The Time... Guys. Knowing the showrunners, this will not go unexplained.
  • U Realms Live: Gnomes and Keen Gnomes have no known reason for existing. They just started appearing after the Birth of Magic, first in small number, then in great enough number that they formed their own societies.
  • From The Adventure Zone: apparently there is a canon reason why Garfield the Deals Warlock was growing a new body for Magnus; however, Griffin has stated that it's funnier and/or creepier to imagine your own answer, and that he will take the canon answer to his grave.
  • C0DA, written by former The Elder Scrolls series writer/designer Michael Kirkbride, takes place in the far distant future of TES universe. It offers a possible explanation to the ES riddle for the ages regarding the disappearance of the Dwemer: the ritual they performed to Ascend to a Higher Plane of Existence turned them into the brass skin of Numidium, the Reality Warping Humongous Mecha they intended to turn into a new god.
  • Creepypastas use this a lot in general. For example, how did kids see the Candle Cove show on TV when all adults saw was static? There were fan sequels that tried to explain this which annoyed the original author who said it's better off with us simply never knowing.

    Western Animation 
  • Adventure Time: Naturally, a show so weird and steeped in its own mythology is bound to have its own set of mysteries:
    • We have a basic idea of the pre-history of the Land of Ooo. Still, what exactly from the Great Mushroom War fallout caused the world to mutate from human civilization into bizarro sentient lifeform potpourri?
    • For a single episode example that will definitely never be explained, was Phlannel Boxingday in the "Lemonhope" two-parter actually Princess Bubblegum in disguise, as is broadly hinted?
  • Archer:
    • Who is Archer's father? The currently known candidates are Jakov, Len Traxler, Buddy Rich and an unnamed Italian man. His real father actually appears in a flashback in "Once Bitten". He never says his name and his face isn't shown, but judging by his voice he isn't any of the aforementioned candidates. Archer is about to say his name after waking up, but forgets before he gets the chance. And then there's the implication the flashback was All Just a Dream.
    • What was in Kenny Loggins' briefcase that cast a purple glow?
    • What was Cyril's name for having stir fry on Fridays before Archer suggests Stir-Friday?
  • Avatar: The Last Airbender:
    • Who were Aang's parents? Since Aang was raised by monks, all we really know about his parents was that they died in the Air Nomad genocide like the rest of the Airbenders.
    • Why do the Gan-Jins and Zhangs really hate each other so much?
    • Did Aang and Katara kiss in "The Cave of Two Lovers"?
  • Used for a character but not the audience in the "Riddler's Reform" episode of Batman: The Animated Series. When Batman is able to escape The Riddler's deathtrap of sealing him in a building that has high explosives in it, the Riddler is so bewildered by Batman's escape that he no longer cares about going to Arkham or losing his now legitimate business and lifestyle and only cares about finding out how Batman was able to survive a trap he clearly shouldn't have been able to. While Bruce later explains it to Dick Grayson — and the audience — back at Wayne Manor, he never explains it to the Riddler himself. Mr. Nygma ends up going even more insane due to not getting an explanation.
  • Batman Beyond refers several times to a Great Offscreen War known as "The Near-apocalypse of '09," but gives very few details, apart from the fact that the notoriously unkillable Ra's al Ghul was supposedly killed during it. The conflict's exact nature is never explored in any part of the DC Animated Universe.
  • Clarence: What ever became of Clarence's actual dad, and will we ever learn what became of him?
  • Code Lyoko: What exactly does Jérémie look like on Lyoko? All we have to go on is Odd and Ulrich's claim that he looks "ridiculous".
  • Codename: Kids Next Door: What was it the Delightful Children did that made Numbuh 1 bald, and why does Numbuh 5 blame herself for it?
  • Ed, Edd n Eddy: What was under Double D's hat?
  • The Fairly OddParents!:
    • What are the names of Timmy's parents? Lampshaded in the episodes "Father Time" and "Shelf Life", which either mute out their names or cut things off right before they're revealed.
    • Who is the mother of Timmy's children Tommy and Tammy at the end of Channel Chasers? note 
  • The last episode of Gravity Falls had a dying Bill Cipher cry out out a backward message to "Axolotl" that he might return. By the creator's admission, this was written as something he could write about laternote , but just as well leave as mystery.
    Alex Hirsch: I like stories that complete their emotional arcs, but still leave some lingering threads to chew on. It gives the fans something to theorize on, and it gives me a window back into that world if I ever choose to return to it.
  • Hey Arnold!: What was the identity and nature of the mysterious tenant Mr. Smith?
  • Inspector Gadget: What does Dr. Claw look like? Almost 20 years after the show ended, his face appeared briefly at the end of the SNES game and an official action figure was released. Cue many disappointed fans.
  • Jimmy Two-Shoes: What is the nature of Miseryville, and where did Jimmy come from? Most fans believe Miseryville is Hell and that Jimmy came to the place by accident, as that was the original pitch, but the show itself never indicates whether that's canon or not.
    • Who is Beezy's mother/Lucius' (possibly ex-)wife? Beezy talked to his grandmother on the phone in an early episode, so clearly Heinouses do have mothers/wives, but other than that, we don't have much to go on. Incidentally, Beezy's mom/Lucius' wife existed in the original concept, but over time, transformed into Lucius' Rich Bitch girlfriend Jez.
  • In Littlest Pet Shop (2012), it's never explained how Blythe's dumbwaiter accident gave her the ability to talk to animals. The most commonly accepted theory is that she bumped her head.
    • At the end of "Littlest Pet Street, Part 2", Roger reveals that he always knew that Blythe could talk to animals, because Betty Baxter, Blythe's mother and Roger's wife, had the same ability, which Blythe inherited from her mom.
  • In My Little Pony: Friendship Is Magic, the Winged Unicorns Celestia and Luna are practically Physical Gods. Where do they come from? The Journal of the Two Sisters suggests they were born to other alicorns (this show's name for Winged Unicorns), but the season six premiere has Celestia and Luna say that alicorn births are beyond their understanding, so it seems like there's no hurry to specify their histories.
    • Moons as units of time have appeared several times in the show, and seem to be some type of microts, but the show staff have deliberately avoided specifics. It doesn't help that the moon doesn't follow a natural cycle in the series, but is manually controlled by the sisters above.
  • Over the Garden Wall: Word of God confirms this was the intention behind the black turtles.
  • Phineas and Ferb:
    • In-Universe example—where exactly do their projects disappear to every day? They even try to work it out in the episode "Don't Even Blink", but (un)fortunately the Doof was working on an invisibility/destruct-inator that day, so they never found out.
    • What is the giant creepy floating baby head? Why does it keep showing up? Lampshaded in the Grand Finale:
    We met Klimpaloon, Meap, and the Lake Nose Monster, but we're still baffled by the Giant Floating Baby Head
    • In a similar vein; the inexplicable talking Zebra that calls Candace 'Kevin'. Only Candace ever seems to see it, and it only appears when she's hallucinating, dreaming, thinks she's hallucinating or dreaming, or when ''somebody else is dreaming that she's dreaming''. That said, he also appeared in an parallel universe. Why can it talk? Why does it seem to know Candace? Why does it call her Kevin?
      • Well, in the strictest sense, it's just Rule of Funny, but still.
    • What is "Ferb" short for?
  • Samurai Jack: What is Jack's real name? Neither the original nor the revival series answer this.
  • The Secret Show:
  • In The Simpsons:
    • In "Two Dozen and One Greyhounds", Bart and Lisa try to escape from Mr. Burns by dropping down a laundry chute he's too big to fit into. But when they land in his mansion's basement, he's already waiting there with a gun.
      Bart: That's impossible! How did you get here first?
      Mr. Burns: Oh, there'll be plenty of time for explanations later.
    • In "The Front", having forgotten his name, Grandpa checks his underwear. When asked how he removed them without removing his pants, he shudders and admits, "I don't know!"
    • In "Monty Can't Buy Me Love", Mr. Burns has gone to Scotland to capture the Loch Ness monster, which swallows him. The next scene shows the monster hanging tied up under Burns's helicopter on their way back to the States. Groundskeeper Willie is impressed that Mr. Burns could subdue the monster.
      Mr. Burns: Yes, I was a bit worried when he swallowed me, but... you know the rest.
    • In "The Last Temptation of Homer", it seemed some Springfield Nuclear Power Plant employees would die of gas poisoning because the emergency exit door was just painted on the wall. Cut to the next scene with one of those employees at Mr. Burns' office telling him he won't bore his boss with the details of their escape and asking for a real door.
    • In "The Seemingly Never-Ending Story", when Edna Krabappel first arrived in Springfield, Moe started dating her. Because she hated taverns, he pretended he wasn't a bartender. He then closed the bar and started tossing the patrons away. As he realized he kept retossing Barney, he asked how Barney came back in. Barney said that, as a drunkard, he doesn't know how he does most stuff he does.
    • Where the Hell Is Springfield?
    • In "Bart on the Road", who is Langdon Alger, Lisa's secret crush?
    • In "Fear of Flying", how or why is Guy Incognito an exact double of Homer? Is he another illegitimate Simpson a lá Herb Powell?
    • In "Lisa the Simpson", what is in the can missing its label at the Kwik-E-Mart? Is it dog food? Soup? Things Man Was Not Meant to Know?
    • In "Homer Goes To College", Krusty shows an "Itchy and Scratchy" cartoon where Scratchy finally gets Itchy. However, the TV is unplugged while Bart and Lisa are watching, and by the time the TV's plugged back in, the cartoon's over with Krusty declaring "They'll never let us show that again! Not in a million years!". How did Scratchy get Itchy?
    • In "King-Size Homer", Homer is trying to prevent an exploding tank at the nuclear power plant, as the catwalk breaks under him. As he's dangling, he says "Wait a minute, there's probably a...", but is thrown into the air by some vented gas, before landing on top of the tank's release tube. How was Homer thinking of stopping the explosion?
    • In "Homer's Triple Bypass", Ned Flanders thanks God for Swingin' to the Oldies, volumes 1, 2 and 4. What was on volume 3 that would make him not thank God for it?
    • "The Man Who Grew Too Much" shows us that Edna Krabappel died at some point, off-screen. When and how she died is never explained, as the character was only killed off out of respect for her voice actress.
    • Where do all the supernatural creatures come from? And why does everyone just ignore them? Why didn't they ignore the angel skeleton in "Lisa the Skeptic" like everything else?
  • Sofia the First:
    • How can anyone's life be saved nine and a half times?
    • The episode "When You Wish Upon a Well" features a wishing well that grants Three Wishes. King Roland's first wish doesn't end well and this is all he says about that wish.
  • SpongeBob SquarePants:
    • What is the secret formula of the Krabby Patty?
    • Who is Pearl's mother, and why is she a whale when her father is a crab?
  • Star Wars Rebels: Where did Ezra and Thrawn disappear off to post-Endor?
  • Teen Titans:
    • The episode "X" involved Red X (a supervillain identity Robin had previously invented as part of a Reverse Mole plan) showing up, with someone we can be pretty darn sure is not Robin under the signature Red X suit. Fans have wondered for some time who the new Red X really is, and Beast Boy came up with a number of theories, but Word of God says Raven came to the only conclusion that mattered:
      Raven: Face it, Red X could be anyone. Anyone smart enough to find the suit and dumb enough to take it for a joyride.
    • The episode "Revved Up" revolved around Robin trying to get back a briefcase that Ding Dong Daddy had stolen from him. When asked what's inside it, Robin just says, "It's personal." When the briefcase is finally opened, its lid fills the entire screen, causing a Smash to Black, the end of the episode, and legions of fanboys/girls demanding to know, "What's in the frikkin' briefcase!!!" Possibly a Shout-Out to Pulp Fiction, where there was also a briefcase integral to the plot that we never find out the contents of.
    • The exact nature of Slade himself is never revealed, and given his liberal use of robot doubles this includes how many times we've seen the real one. In the comics he is simply Slade Wilson, a mercenary and criminal mastermind also known as Deathstroke, but it is never stated if this is true for the animated version as well.
    • Was the mysterious girl in the Mind Screw final episode really a resurrected Terra?
  • Transformers Animated: What part of Starscream's personality does Slipstream represent?
  • The Venture Bros.:
    • What did Rusty Venture do to make the Monarch hate him so much? Lampshaded in one episode when Tim-Tom and Kevin question Dr. Girlfriend about it, only to realise they're not going to get a straight answer from her.
    • What was the purpose and function of the ORB? Who built it? Nobody knows and nobody ever will know now. The creators have admitted that they were basically trolling the viewers with this one and will probably never get around to answering it.
  • Xavier: Renegade Angel: What the hell is Xavier? And how did two seemingly normal humans have one as a child?