History Main / MarsNeedsWater

* A variation in ''Film/ItTheTerrorFromBeyondSpace''. An autopsy shows that a victim of the monster from Mars was dehydrated of water and every other fluid, and the crew speculate that the creature has to take on water by feeding on smaller creatures that collect water from the soil.

* A variation in ''Film/ItTheTerrorFromBeyondSpace''. An autopsy shows that a victim of the monster from Mars was dehydrated, and the crew speculate that the creature has to take on water by feeding on smaller creatures that collect water from the soil.

* In ''Film/BattleLosAngeles'' the alien invaders seem to be sucking up the oceans.

[[folder:Newspaper Comics]]
* A ''ComicStrip/CalvinAndHobbes'' strip parodies this with a poem Calvin wrote about a flying saucer stealing the Earth's water and air, which ends in a heavy-handed GreenAesop by comparing this to human destruction of the biosphere.
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->''"Pure liquid H-2-0 is the rarest and most valuable commodity you can imagine. It's one of the first resources any industrial society destroys and pollutes. You've already started here, so you should know. Unlike most planets, ours included, your world has a lot more water than it has land area. We need water desperately--for sustenance, industry... everything."''

[[folder:Web Comics]]

** Played with in "Ocean Gem": Lapis Lazuli steals the Earth's oceans, but not for any chemical use--she wanted to get back to her home planet, and thought using her [[PersonOfMassDestruction super-powerful]] [[MakingASplash hydrokinesis]] to build a StarScraper was the best option. It still wasn't nearly enough.

* The invading aliens in ''Film/TheFaculty'' are an aquatic species that needs a lot of water and whose original planet dried up. One sign that someone is infected by the PuppeteerParasites is a need to drink lots of water, and dehydrating them quickly via a special drug based off caffeine pills turns out to be a means of killing them quickly.

* In ''Series/{{V 1983}}'', the Visitors are after Earth's water, and the fact that [[ToServeMan humans are delicious]] too doesn't hurt. The {{Novelization}} has a [[JustifiedTrope justification]]; in this {{Verse}}, the industrial effort of interstellar space development [[TerraDeforming irreversibly destroys biospheres]], and they have been unable to develop water purification technologies capable of efficiently supporting millions, let alone billions of people. Thus, the resulting empires are not only constantly fighting over whatever ''relatively pure'' water remains, but ''food'' as well; maybe they could harvest water from undefended comets(after filtering out twenty percent of their weight in [[{{Squick}} ammonia]][[note]]Though in real life, ammonia is actually a very useful chemical, to the point that [[https://en.wikipedia.org/wiki/Haber_process there's an entire industrial process for making it]]. If anything, the ammonia in comets should make them ''more'' attractive to a spacefaring society.[[/note]]), but a life-sustaining world which not only has over a quadrillion tons of fairly clean water but four and a half billion two-hundred-pound food animals too stupid to colonize space themselves? The planet looks like a buffet table guarded by illiterate street punks. And the Visitors have [[SlowLaser Slow Lasers]]... which happen to be fusion powered and need heavy water as fuel. [[note]]Heavy water has deuterium instead of regular hydrogen - about 115 in every million water molecules are heavy, regardless of where the water comes from, so they could use space-harvested water for that and for at least some industrial stuff. But where's the fun in that?[[/note]]

[[ArtisticLicenseSpace Realistically, invading Earth isn't a smart way to get water]] as there are a variety of other more easily accessible locations in space. All comets and a variety of asteroids, moons, and even large, interstellar clouds have water in great abundance and are much more accessible and easy to harvest than Earth, as well as lacking those pesky hairless apes. (For instance, [[UsefulNotes/TheMoonsOfJupiter Europa]] has a water ocean ''60 miles deep''.) Occasionally, this will be justified (or handwaved) through an explanation that Earth's water somehow has some quality that other sources lack.

* In ''Series/{{V 1983}}'' the Visitors are after Earth's water, and the fact that [[ToServeMan humans are delicious]] too doesn't hurt. The {{Novelization}} has a [[JustifiedTrope justification]]; in this {{Verse}}, the industrial effort of interstellar space development [[TerraDeforming irreversibly destroys biospheres]], and they have been unable to develop water purification technologies capable of efficiently supporting millions, let alone billions of people. Thus, the resulting empires are not only constantly fighting over whatever ''relatively pure'' water remains, but ''food'' as well; maybe they could harvest water from undefended comets(after filtering out twenty percent of their weight in [[{{Squick}} ammonia]][[note]]Though in real life, ammonia is actually a very useful chemical, to the point that [[https://en.wikipedia.org/wiki/Haber_process there's an entire industrial process for making it]]. If anything, the ammonia in comets should make them ''more'' attractive to a spacefaring society.[[/note]]), but a life-sustaining world which not only has over a quadrillion tons of fairly clean water but four and a half billion two-hundred-pound food animals too stupid to colonize space themselves? The planet looks like a buffet table guarded by illiterate street punks. And the Visitors have [[SlowLaser Slow Lasers]]... which happen to be fusion powered and need heavy water as fuel. [[note]]Heavy water has deuterium instead of regular hydrogen - about 115 in every million water molecules are heavy, regardless of where the water comes from, so they could use space-harvested water for that and for at least some industrial stuff. But where's the fun in that?[[/note]]
* In the pilot episode of ''Series/StarTrekVoyager'' the Kazon-Ogla seek water because they're in a region of space without it, thanks to the environmental disaster inadvertently caused by the Caretaker. The crew of Voyager agree to trade water for information on the region, but unwisely explain that they can create water with their amazing replicator technology that the Kazon spend the next two years trying to get their hands on.

* ''Series/{{FlashGordon|2007}}'': In the Creator/SyFyChannel remake Mongo's water supply was contaminated by a nuclear accident and Ming uses the last pure well on the planet to control the various peoples of Mongo. Unfortunately it's running dry, so he turns to Earth.

[[folder:Art]]
* Inverted in [[https://www.zazzle.com.au/water_on_mars_poster-228072988376343371 this]] mock {{retraux}} movie poster by Steve Thomas.
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