"Dinosaurs are extinct, so you never can tell where you'll find them."
Everyone knows that dragons (or elves, or fairies, or Prehistoric Monsters
, or whatever race it may be) have been extinct for thousands of years...but if they're all gone, why is this story taking such pains to mention them? It's a safe bet that they aren't extinct at all, and that you'll meet one by the end of the story (if not sooner).
Also applies if the creature in question is thought to be a myth. A form of Chekhov's Gun
. May involve an Egg McGuffin
This is generally a fantasy trope. If it happens in the real world, or if the story revolves around an extinct creature being discovered, it's Species Lost and Found
- In Negima!?, Asuna spends 24 out of 26 episodes looking the Chupacabra which everyone says doesn't exist; they create a Chupacabra school club and order T-shirts and other items. At the end of the series, she finds one (which she quickly puts to work signing T-shirts.)
- Downplayed in Harry Potter. Word of God states that while none of the creatures Luna "Looney" Lovegood claims exist actually exist, the fact that she accepts their existence helped her in discovering many real magical creatures that were previously unknown.
- In Fantastic Beasts and Where to Find Them, Dodos are actually magical creatures who used their powers to avoid Muggles after the Muggles started hunting them. Only the Muggles still believe they are extinct.
- In The Hollows, it's widely believed that elves were wiped out in the Turn, but a few survived, including Trent, Jonathan, and Quen.
- On the Discworld a lot of standard fantasy creatures are extinct, though that's often synonymous with "trapped in a parallel dimension."
- Giant, flying, fire-breathing dragons are shunted off in a dimension of their own. Their improbable biology requires magic to sustain, and the Discworld generally doesn't have enough magical energy around for them to exist anymore. There are exceptions, small pockets of high magic where dragons survive, and individual dragons can be summoned if enough magical energy is pumped into them.
- Elves are similarly stuck in their own dimension(s), although there are weak points where travel is possible - lots of them in the Ramtop mountains.
- Orks were the foot soldiers of the defunct Evil Empire, and it's revealed in Unseen Academicals that the people of Uberwald have been exterminating the few survivors. They haven't been entirely successful.
- Animorphs does this with the Venber in The Extreme. Though they're actually hybrids of Venber and humans brought back by the Yeerks.
- In the Ravenloft novel Scholar of Decay, a wizard exploring some underground passages in Richemulot has a brief encounter with a black pudding, a D&D monster not at all typical of the Gothic Horror-style Land of Mists. He avoids it, then pauses to marvel at its presence, as they're considered to be extinct.
- In Tamora Pierce's The Immortals series, all sorts of species of magical creatures are coming back from exile in the Divine Realms where they had been locked by human mages so long ago that people had started to think they were just myths. The stories show the humans learning to deal with the chaos that ensues.
- In China Miéville's The Scar, the discovery that Bas-Lag's ancient race of anophelii (mosquito-folk) aren't extinct comes as a shock to many in Armada. Soon enough, an Armadan diplomatic party goes to visit them, and brings one back with them.
- In the Conan the Barbarian story "The Devil In Iron", Conan ventures into a mysterious city on an island that'd previously held only ruins. His suspicion that something has brought the long-dead settlement back to life is supported when he finds the intact pelt of a golden leopard in a bedchamber, and recognizes it as an animal that went extinct a thousand years ago. He later fights a giant snake, also of a species known to be extinct.
- Game of Thrones has two explicit examples of creatures widely believed to be extinct at the start, namely dragons and the White Walkers. People are... less sure by the end of the first season on the second count, with the first count being deliberately proven false in the first season finale. In the second season finale, implications are proven to be completely correct on the second count, with an Army of the Dead finally seen amassing for an eventual assault on the South.
- Supernatural: The attack pattern of the Monster of the Week points to a dragon, but dragons are extinct...except this one.
- When they first appear, vampires are said to be all but extinct, but they have quite a few appearances through out the series.
- Stargate SG-1's first-season episode "Thor's Hammer" has the Unas, the first species taken as hosts by the Goa'uld. Upon their first encounter with the Unas in the labyrinth, Teal'c tells it, "You do not exist." He was wrong about Goa'uld-infested Unas' ability to regenerate from massive amounts of injury, too.
- The Dragon Age series takes its name from the fact that dragons were believed to be extinct for the last several centuries (not counting the Archdemons, who take the form of dragons). They reappeared at the start of the current age.
- In Firan MUX, it was largely believed that griffons, one of the favoured creatures of Zutiv, were merely mythological creatures. Then the Shamibelians invaded from griffonback. As of the start of the game, they're so common they almost replace horses as a cavalry unit.
- In Touhou, it's widely believed that there are no oni in Gensokyo despite otherwise being a Fantasy Kitchen Sink. And then of course they immediately meet one. In fact, it's not even mentioned until they meet her and it comes up in their conversation with her as Arbitrary Skepticism.
- In the beginning of The Elder Scrolls V: Skyrim no one has seen a dragon in centuries. The fact that they're coming back kicks off the main quest line, and you eventually find out that while some did survive undetected for centuries most of them are actually being brought Back from the Dead by Alduin, the Big Bad.
- There's also the Snow Elves, who have degenerated into the Falmer after being displaced by the Nord race of men and sheltered by the Dwemer, who proceeded to blind, mutate and enslave them. The Falmer themselves were thought to just be a myth for years until they began raiding the surface again, and then there are two original, non-mutated Snow Elves who you meet during the Dawnguard expansion.