An Ending Trope common to {{B Movie}}s of the '50s and '60s, especially those involving a LostWorld, in which an earthquake, volcano, avalanche or some similar (usually natural) disaster destroys the LostWorld. This can be [[ChekhovsGun hinted at in advance]], but as often as not it appears out of the blue to threaten the main characters and necessitate a hasty departure. For some reason, the disaster always manages to hold off just long enough for the characters to actually discover the LostWorld and explore for a bit, then literally yanks the ground out from under them.

Of course, in a few cases the cataclysm is actually not a coincidence, but indeed is triggered by the protagonists. In these cases it's usually unintentional; it could be the heroes' very presence which somehow disrupts the natural balance. Or, sometimes it is set off by some act done by the villains, or occasionally the heroes -- say, a stray bullet/laser blast/etc meant for the heroes instead hits a support structure or [[CosmicKeystone the ancient codex holding the world together]] or what have you. Crash!

If the LostWorld in question is an island, an underground society or otherwise isolated location, expect it to be leveled by the cataclysm. If it is a planet, the whole world need not be destroyed; but [[EarthShatteringKaboom this has been known to happen]].

Like the {{B Movie}}s it was usually part of, the "natural" version of this sort of ending is practically a ForgottenTrope nowadays. The "triggered" instance, [[UndeadHorseTrope on the other hand...]]

Compare TrashTheSet. If it happens specifically because the {{Villain}} has just died, you have a LoadBearingBoss.

* ''Anime/TheFumaConspiracy'' has the entire cave is rigged to collapse. The heroes make it out alive, but all the treasures are lost.
* [[InvokedTrope Invoked]] twice in ''Anime/NeonGenesisEvangelion''. [[spoiler: The Second Impact was a less successful invocation, but come Third Impact, AssimilationPlot, TheEndOfTheWorldAsWeKnowIt, and KillEmAll are all in play.]]

* The ''Franchise/{{Tintin}}'' [[Recap/TintinFlight714 story "Flight 714"]] ends like this, in true B-Movie fashion.

* ''Film/LostContinent'': At the end, the island which serves as the film's primary setting just explodes like Krakatoa; there are hints that underground volcanic pressures are responsible.
* ''The Incredible Petrified World'': The cast, seeking an underground refuge from a potential nuclear holocaust, find an entire ecosphere deep within the earth... which quickly caves in for no apparent reason.
* ''Film/KingDinosaur'' (just one island, though, and it's because the heroes decided to nuke their prospective space colony)
* ''Franchise/IndianaJones'':
** ''Film/IndianaJonesAndTheLastCrusade'' - Dr. Elsa Schneider tries to take the holy grail past "The Great Seal," which causes the entire temple to fall apart with a local earthquake. This sets up a TakeMyHand moment where she tries to reach for the grail while hanging onto Indiana. She can't quite touch it and experiences a DeathByMaterialism. Indiana nearly does the same but decides to let it go.
** Justified in ''Film/IndianaJonesAndTheKingdomOfTheCrystalSkull''.
** ''Videogame/IndianaJonesAndTheFateOfAtlantis''. What is it with Indy and Lost Worlds?
* ''Film/KingKong'':
** In ''Film/KingKong2005'', this is Skull Island's ultimate fate. Note, however, that this factoid was revealed only [[ExpandedUniverse on the official promotional website]], not in the film itself.
** This idea was taken from the climax of ''Film/TheSonOfKong'', the mostly forgotten sequel to the original ''Film/KingKong1933''.
* Rare example of a ''deliberately'' triggered cataclysm: ''Film/ForbiddenPlanet'', via the planet's SelfDestructMechanism.
* Another deliberate disaster: the destruction of Metalluna in ''Film/ThisIslandEarth''. Granted, that wasn't the end of the movie, per se, but it fits the trope in every other way.
* ''Film/BeneathThePlanetOfTheApes''. This is what happens when the LostWorld is an entire planet. You'd think blowing up the entire world would put a stop to any future sequels. [[UnCancelled You'd be wrong.]]
* ''Film/Terminator3RiseOfTheMachines'' doesn't end with the planet being destroyed, but the massive nuclear launch at the end of the film does effectively end civilization.
* In ''Disney/TreasurePlanet'', the title planet is actually a giant self-destructing explosive device, and the climax involves the main characters attempting to escape the planet before it explodes.
* The 2008 version of ''Film/JourneyToTheCenterOfTheEarth'' ends with the area of plant life being burnt to a crisp. It seems that it's cyclical in nature and it may be possible to go back in another 50 years; but with all the magma the flooded the area its hard to imagine how.
* The climax to ''Film/OneMillionYearsBC'' is the caveman tribes being threatened by a massive earthquake.
* ''Film/HerculesAndTheCaptiveWomen'': Hercules destroys the Evil Queen's Magical Cave Of Doom... which takes all of {{Atlantis}} with it.
* ''Film/UnderseaKingdom'': Atlantis, an underwater city, is flooded and destroyed [[note]]again![[/note]] when the villain punches an escape vent through the city's protective shell.

* ''Literature/TheMysteriousIsland'' ends with Lincoln Island being destroyed by a volcanic eruption.
* The first book of the ''Literature/CambridgeLatinCourse'' is set in Pompeii. In the year 79 CE. That the last chapter is a Cataclysm Climax [[YouShouldKnowThisAlready should surprise no one]].
* T. A. Barron's ''Heartlight'' [[DownerEnding ends with]] the alien world the heroine visits being [[ApocalypseWow swallowed by its sun, which has become a black hole]].

* It appeared that ''Series/{{Lost}}'' would end like that for a while: starting with a mention of a volcano being present on the Island, then the Island being shown submerged underwater in the FlashSideways and finally the Man In Black intending to destroy the Island near the end. The Finale appears to play this straight: after the Island's Heart is disturbed, it is shaken by massive earthquakes and several cliffs collapse into the Ocean before the majority of the heroes make their escape. The Trope is then subverted, when the Island's Cork is put back in place (no kidding) and the cataclysm is stopped.
* The endings of most [[DinosaurMedia dino-documentaries]] involve the asteriod ending the Mesozoic era.

* The ending of ''VideoGame/Uncharted2AmongThieves'' sees the destruction of the [[spoiler:Lost City of Shambhala thanks to Nate blowing up the Tree of Life in the final boss battle against Lazarevic]].
** Done again in ''VideoGame/Uncharted3DrakesDeception'' [[spoiler:When Ubar is swallowed by the sand due to the central pillar being destroyed]]. [[spoiler: With ''THREE GODDAMNED BULLETS!'']]
* In ''VideoGame/RivenTheSequelToMyst'', [[spoiler:you cause this yourself. Deliberately, under orders from Atrus.]]
** Not exactly. Atrus tells you to [[spoiler: "signal me and I'll bring a linking book" but it's Catherine who tells you that opening the Star Fissure will do that.]]
* Averting this trope is the main objective in ''Return to Mysterious Island 2: Mina's Fate''. [[spoiler: In fact, you get the option of averting it ''twice'': once by stopping a volcanic eruption triggered by the previous game's events, and again by choosing to protect the island's ecosystem by restoring the shield Mina deactivated in the first game.]]
* At the end of ''VideoGame/{{Earth 2150}}'' the Earth is sent hurling into the Sun, while the factions ships escape.
** Of course, this is not only hinted but outright stated in advance. In fact, your goal for the entire game is to collect enough resources in a certain number of days to build a ship/fleet large enough to take your entire faction to Mars. The fact that the planet keeps looking worse and worse and the various news reports only serves to beat you over the head with the fact.