[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/Waters_of_Mars1_3234.jpg]]

->''We're not just fighting flood... we're fighting time itself! '''[[BadassBoast And I'm gonna win!]]''' ''
--> '''The Doctor'''

The Doctor steps out onto the surface of Mars, wearing [[{{Recap/DoctorWhoNSS2E8TheImpossiblePlanet}} a very]] [[{{Recap/DoctorWhoNSS3E742}} familiar]] space suit. He's come to Mars on a whim, and quickly finds himself looking upon a human colony called [[Music/DavidBowie Bowie Base One]]. He's captured right away, though, by a [[RobotBuddy little robot]] named Gadget and taken to see the person in charge of the base: Captain Adelaide Brooke.

The Doctor thinks that the cutesy robot is rubbish (although robot ''dogs'' are cool, of course), but otherwise loves the base. It doesn't take long for the Doctor to realize exactly where he is, and ''when'': November 21st, 2059. Captain Brooke and her crew are the first human colony on Mars. The Doctor is a huge fan of their trip, and as he rambles through their history while madly {{squee}}ing, we see flashbacks to a series of articles with obituaries. [[KillEmAll The crew will die here today.]] The Doctor knows it -- and knows that he shouldn't interfere, because this is a tremendously important fixed point in time. He'll never know what kind of monster attacked them, but that's fine, and he'll just leave now.

And indeed, people go missing. One named Andy is already dead. Another, Maggie, is found conked on the head. She's taken off to the medical dome. The Doctor should leave now. But he lets himself be roped into the investigation by Adelaide, into the Bio Sphere, joined by [[RedShirt Expendable Crewman]] Tarak. Within a good few minutes, Tarak is separated from the Doctor and finds what appears to be Andy... water flowing off of Andy like he's a theme park ride. Andy's face is distorted, cracked, and gushing water.

The Doctor keeps making vague excuses about how he has to go.

Maggie, deep in an isolation room, also shows signs of... whatever this is. She's freaking out the base's medic, Yuri. He contacts Adelaide, and she realizes it's best to leave the dark, scary giant building with lots of places for something to jump out at them. But they make one last look around for Tarak... and find him. In the same water-zombie state as Andy, who is standing right next to him, or what used to be him. Dragging Adelaide away, the Doctor announces it's time to run, and they barely escape the two infected humans. (The Doctor suggests bicycles for future missions. Bicycles are cool.)

They locking the two infected forms out of the main central dome. These water creatures, Maggie included, are demanding to go to Earth -- where they can thrive in water. The Doctor raises up the question of who ''else'' is infected, if the virus/parasite/whatever isn't inside everyone else on the base already, as it thrives in the water and obviously came from the Martian water that everyone has been drinking. Adelaide goes off to check the ice cap that this base is built on top of, while the rest of the crew begin prepping for escape to Earth. The Doctor knows that he should be ''leaving''. But he decides to instead run off and join Adelaide instead, seeing as he can't leave without his spacesuit.

At the ice cap water extraction dome, the Doctor and Adelaide look out over a rather impressive ice cap while the Doctor rambles about [[ContinuityNod an old enemy of his]] -- the Ice Warriors. Adelaide begins to question the Doctor about why he's so eager to leave and how he knows so much about the Mars colony. The Doctor explains that this is a "locked moment in time," confusing the hell out of Adelaide for a few moments before the Doctor quickly changes the subject to ''why'' Adelaide came out into space: [[{{Recap/DoctorWhoNSS4E12TheStolenEarth}} The Dalek Invasion of 2009]]. She looked into the eyestalk of a Dalek, it looked right back, and left her to live. Adelaide simply wished to follow that Dalek out again -- not to kill it, but to meet other creatures in peace.

The Doctor rambles on about how awesome Adelaide's descendants will be, all inspired by her heroic journey to Mars. And how massively important they'll all be to the future of all time and space. More newspaper flashbacks. It freaks the hell out of Adelaide in general. In seconds, though, it's revealed that everyone else still alive doesn't happen to have the virus -- so it's time to start leaving!

...or it would be, if the infected bodies that were once Andy and Tarak didn't somehow climb up on top of the central command building to start spewing water everywhere.

The Doctor, now with space suit, finally starts to leave. But Adelaide refuses to open up the airlock hatch until the Doctor explains why he's being so... awkward around everyone. He explains it all for us (and Adelaide): ''this very day'' is the day that Bowie Base One is destroyed with all hands lost. Adelaide's heroic death is what will inspire her descendants and what will propel humanity into interstellar travel. It has to happen.

The Doctor leaves solemnly, listening through his helmet to the attempts of the remaining cast to fight fate the best they can. He hears about the water seeping into the main control room, taking out another member of the cast. Yet another cast member is infected as a single drop hits his face -- and this one demands the crew leave him before he's infected. The pilot of the shuttle, Ed, is also infected -- but [[HeroicSacrifice chooses to blow up the shuttle]] rather than let the Earth get infected. The resulting explosion traps our remaining three castmembers in a single storage room, and knocks the Doctor quite a good distance.

All looks grim for Adelaide, Yuri and Mia... until the Doctor walks into the storage room, shouting out orders like a maniac and trying to save those people he'd declared dead. Adelaide begins to panic, wondering why the Doctor is throwing his previous worries out the window. Almost foaming at the mouth, the Doctor launches into a speech about how there are laws of time. But he can warp them. And he's safe, he knows it's not his time yet, because he'll be killed when someone knocks four times. So today, he's decided that EverybodyLives. The laws of time that were once enforced by a group of people -- a group long since dead...

->"''Do you know who that leaves? ME!! It's taken me all these years to realize it, but all those laws of time are mine. '''And they will obey ME!!!''' ''"

Adelaide, reasonably enough, believes that the Doctor's gone insane. The Doctor declares he's also ''fighting time itself.'' Not even close to giving up, the Doctor finds that robot buddy Gadget in storage and uses it to bring the TARDIS to him -- even while Adelaide sets the base to self-destruct. With four seconds to go, the TARDIS begins to re-materialize. As it finishes, the countdown reaches zero...

...but everyone left actually ''survives'', as the TARDIS arrived just in time. The Doctor takes the survivors to Earth: same time, same day. Mia, unlike many companions of the past, ''utterly freaks out'' at the TARDIS itself and flees -- Yuri running after her. The Doctor himself is all grins and smiles, proudly proclaiming how time now obeys him. He give himself the new title of [[AGodAmI Time Lord Victorious]]. Not only did he save two of the "little people," but he also saved one of the "big ones".

Adelaide does not take this well, trying to reason with the Doctor -- claiming that no one person should have so much power. However, she just cannot get through to him, as the Doctor is finally realizing everything that he can do, all that he can accomplish. He can warp time, escape death, [[ArsonMurderAndJaywalking open up the door to Adelaide's home]].

Adelaide simply glares at the Doctor and enters her own home. A blue flash through her windows [[HeroicSacrifice makes it perfectly clear what she did]]. The Doctor finds himself suddenly remembering a new set of newspaper articles: Adelaide's death on Earth, the surviving crewmembers paying tribute to her heroism, and then her descendants, inspired by her example, continuing on exactly as before the Doctor started messing with things.

The Doctor [[GoMadFromTheRevelation breaks]], [[MyGodWhatHaveIDone realizing that he's gone too far]]. [[{{Recap/DoctorWhoNSS4E3PlanetOfTheOod}} Ood Sigma]] appears for a moment, and the Doctor questions the Ood, wondering if this is his time. If now is when he's supposed to die.

Ood Sigma simply vanishes, leaving a distressed and panicked Doctor to dash into the TARDIS and lock the door behind him. The Cloister Bell begins to go off, but the Doctor declares "no" and valiantly throws himself into the next episode preview.

----
!!Tropes
* TheAestheticsOfTechnology: Although the Doctor is using a spacesuit from humanity's future, it doesn't look like it, making the comment on its advanced technology a bit odd.
** Presumably because its more lightweight and noticably less bulky than the suits they are using, which would go some way to why they wonder where it came from.
* BelligerentSexualTension: Its heavily implied that something may have gone on between Adelaide and Ed that ended very badly, hence why their relationship is extremely tense.
* BodyHorror: The people becoming water-bloated, ruptured-skin-sporting, dead-eye-having monstrosities.
* CallBack: To "The Fires Of Pompeii", the last time fixed points in time were mentioned.
** The Doctor is also wearing the spacesuit from Sanctuary Base 6, as seen in "The Impossible Planet".
* ChekhovsGun: The Gadget robot.
* ChronicHeroSyndrome: Really gets to the Doctor in this episode. The Bowie Base One disaster is a fixed event, and as such he would've been more rational and just left right away, but Adelaide forces him to get just involved enough to let his heroic instinct get to him.
* ContinuityNod: Given that they have a good 45 years to work with, this is to be expected...
** In particular, the Doctor's mention of the Ice Warriors - notably the humans regard the idea of a sentient race once living on Mars with scepticism.
** And the Doctor mentions what happened [[{{Recap/DoctorWhoNSS4E2TheFiresofPompeii}} the last time]] he tried changing a "fixed point" in time.
** This isn't the first time this Doctor has met a [[{{Recap/DoctorWhoNSS2E3SchoolReunion}} "funny robot"...]]
*** Is it at all possible that was a slam against Kamelion?
* CreatorProvincialism: Averted for once; while there still seem to be a disproportionate number of Britons around, there is a realistic international representation including the major space powers of the United States and Russia.
** Many countries that are currently not too important on the world stage are described as being major powers after an 'oil apocalypse' which is never really explained (it only gets a brief mention from Adelaide in which she describes that the human race was almost wiped out). Two of these are Spain and the Philippines.
* CuteMachines: Gadget.
* {{Deconstruction}}: The ending essentially deconstructs the Doctor himself and the mythology surrounding him. As with pretty much every episode ever, he saves the day, does the impossible, gets a little bit smug about it afterwards and all-in-all lives up to titles like the "Lonely God" -- and far from being charming and admirable it's creepy and unsettling, because he's also in the process of completely losing touch with the "little people" surrounding him as a result.
* DoNotGoGentle: The Doctor!
* EldritchAbomination via [[OurZombiesAredifferent parasites in the Martian water that turn people into craggy, water-spewing Zombies]]. With unholy screams that can free the ''real'' EldritchAbomination hiding deep within the ice.
* ExtyYearsFromNow: The story takes place on 21 November 2059. RTD gambled on the episode airing on 21 November 2009 and lost, but it's close enough.
* FaceRevealingTurn: Played straight this time, the background music swells as Tarak approaches the now-infected Andy and he turns his face to the camera.
* FakeAmerican: Mia Bennett was born in Houston, Texas, but her actress GemmaChan uses her native English accent.
* FakeRussian: Aleksander Mikic, who plays Yuri, is from Bosnia.
* ForegoneConclusion: You are told upon meeting the supporting characters that they all die. ''Today''. [[OhCrap Yeah]].
* {{Foreshadowing}}: During his AGodAmI stage, the Doctor starts acting like the [[spoiler: Time Lords who appear two episodes later (Same ScrewTheRulesIMakeThem personality).]]
** [[spoiler: Also during his brief reign on terror, he uses some of The Master's quotes. Guess who also shows up a few episodes later?]]
** [[spoiler: When Adelaide heads into her house, we see her draw her pistol. Had the Doctor been paying attention to her instead of ranting to himself, he might have stopped her from killing herself. Then again, if he had been paying attention to her '''at all''', he would have realized how distraught she was and possibly got the idea that going AGodAmI on her was a bad idea.]]
* ForgotICouldChangeTheRules: Inverted/deconstructed. The Doctor really ''can't'' change the rules, at least without causing seven kinds of hell to break loose, but he temporarily forgets this.
-->'''The Doctor''': The laws of time are mine! And ''they will obey me!''
* GlassShatteringSound: The zombies' roars cause the glacier to crack.
* AGodAmI: The Doctor seems to be resembling the Master more at this point. A much ''nicer'' Master, to be sure, but still far darker and morally questionable than before. He also starts thinking of himself as the Time Lord Victorious and talking in such a way that suggests he thinks all of time and space is going to bend to his will.
** For those who didn't get the point, bear in mind that the Doctor's comment about how the laws of Time will obey him is eerily similar to the Master's old CatchPhrase of "I am the Master, and you will obey me!"
* GoMadFromTheRevelation: A subtle execution of the trope - but it certainly applies when the Doctor realizes he changed nothing at all in the long run, in spite of his efforts.
** Arguably what happened to [[spoiler: Adelaide Brooke]] as well. Despite what the entry below says, maybe [[spoiler: she wasn't a HeroicSacrifice at all; maybe she just freaked out at the thought of a sappy eccentric guy playing God and saving peoples' lives based on simply whether they are important or not...]]
* HypocriticalHumor: "I don't like funny robots."
** As well as "Oh, well robot ''dogs'' are different!"
* HeroicSacrifice: One played straight, one subverted in that the sacrifice [[spoiler:wasn't to prevent something from happening, but to keep the time-line intact... or considering that Adelaide's death was changed from a straight sacrifice on Mars to suicide on Earth, is it? It could also be interpreted as heroically sacrificing herself to save the world from the horrors of the Time Lord Victorious.]]
** Ed who detonates the rocket to stop the Flood from reaching Earth when he realises that its on-board and its infected him.
* InformedAbility: While the off-screen sprays of water are obviously damned powerful, the on-screen water sprays don't even look like they get close to the power of a fire hose. Still looks damned creepy, though.
** RealityIsUnrealistic: The water sprays were actually made by fire hoses.
* InMemoriam: To long-time ''Who'' alum [[http://en.wikipedia.org/wiki/Barry_Letts Barry Letts]].[[note]]He worked on the TV series from 1967 until 1981, and wrote radio plays and novels in the 1990s and 2000s. He was pretty much ''the'' guy who chose TomBaker to be the Fourth Doctor.[[/note]]
* JumpingOffTheSlipperySlope: The Doctor's begins to do this at the end, with a truly terrifying MotiveRant.
--> '''Doctor''': There are laws, laws of time. And once upon a time there were people in charge of those laws, but they ''died!''. All of them died! And do you know who that leaves? ''ME!'' Its taken all these years to realise it, but the laws of time are ''mine!'' And they ''will OBEY me!''
* KillEmAll: A ForegoneConclusion. [[spoiler:Which is then subverted, when the Doctor saves three of them! Yes, Adelaide kills herself, but Yuri and Mia are still alive at the end.]]
* KnightTemplar: The Doctor becomes this for the laws of time. It doesn't end well.
* LargeHam: Tennant. You'll know it when you see it.
* MakingASplash
* MeaningfulBackgroundEvent:
** Andy bites a carrot, then the shot changes to focus on Maggie. He remains out-of-focus in the background, convulsing and suddenly falling still.
** Same thing happens to Maggie later, with Yuri in the foreground.
* MultinationalTeam: The astronauts on the base. Several British and American, a German, a Russian, a Pakistani, an Australian and whatever Mia was. FreezeFrameBonus told us she was Korean-American (there's a South Korean flag sticker on one wall and her obituary said she was born in Houston and studied in Stanford), but GemmaChan doesn't put a whole hell of a lot of effort into hiding her accent (and possibly didn't know she needed to. The obituaries were likely made during post-production; it's possible that they made the decision to have Mia be from Texas long after filming).
* MyGodWhatHaveIDone: Going hand-in-hand with GoMadFromTheRevelation, when the Doctor realizes he let his arrogance go to his head.
* NeverTrustATrailer: One of the trailers shows the Doctor mentioning the prophecy from the previous special ("he will knock four times"), just before some knocking starts. In the actual episode, it's only one of the water creatures and it only knocks three times.
-->"And three knocks is all you get!"
* NiceJobBreakingItHero: Good work telling Adelaide what her death would cause Doctor. [[spoiler:If he'd kept his mouth shut, she wouldn't have killed herself to maintain the old timeline]].
* NoodleIncident: Some incident to inspire animosity between Adelaide and her number two is alluded to but never elaborated on.
* NoOSHACompliance: Whoever decided that a room that was meant to ''Quarantine'' people should have a ''basic'' seal and not a Hardinger Seal, clearly didn't understand why an unbreakable seal would help to keep something ''contained''.
* NotSoDifferent: Many an IronicEcho abounds when the Doctor starts to snap and unknowingly begins to channel the Master.
* OhCrap: There are several moments of this throughout the story, considering only ''one'' drop of water can infect someone. The biggest one is at the end, though: the Doctor, on his way back to the TARDIS, pretty much loses it when he realizes Adelaide has killed herself.
* OmniscientMoralityLicense: Deconstructed. The Doctor becomes so overwrought with the guilt and fear that everyone is supposed to die in the expedition, he ''snaps'' and saves the three remaining members whom ''he himself'' categorises as two "little people" plus one "big person". The Doctor declares himself "[[AGodAmI Time Lord Victorious]]", and says there's nothing anyone can do to stop him. Until Adelaide, who is, quite frankly, disgusted with this notion (and rightly so) ''does'' manage to stop him by committing suicide, ensuring that her descendants lead the human race outside the cosmos, and the time-line is somewhat fixed. It took this to realise The Doctor's hubris had ''[[MyGodWhatHaveIDone completely]]'' [[MyGodWhatHaveIDone got the better of him]].
* OOCIsSeriousBusiness:
** Adelaide actually paying someone a compliment is noted to be a bad sign.
** The Doctor going Time Lord Victorious awesome, and ''scary''. Also, his solution to the problem is to use the TARDIS, something he almost ''never'' does.
* OurZombiesAreDifferent: See the entry for EldritchAbomination, above.
* PokemonSpeak: Gadget gadget!
* PreAssKickingOneLiner: "I don't hear anyone knocking!" *...knock...knock...knock* "Three knocks is all you'll get!"
* RealLifeWritesThePlot. When the bio-dome scenes were being shot, the film lights woke up the birds, and a line was added to the script to explain the birdsong.
* TheRedPlanet
* RippleEffectProofMemory: Yes and no; the Doctor's memories of history change at the end, but he seems to be aware that they've changed, and from what.
* RobotBuddy: Gadget
* RunningGag: The Doctor's insistence that they should have brought bikes. Also a LampshadeHanging on the amount of running that goes on in this show.
** The Doctor commenting that he really ''should'' go.
* ScrewTheRulesIMakeThem: Sums up the Doctor's speech.
* SelfDeprecation: Again, the Doctor [[{{Recap/DoctorWhoNSS2E3SchoolReunion}} "doesn't like funny robots".]]
** He does avoid self-deprecation later on by saying that robot dogs are different, making it closer to HypocriticalHumor.
* ShoutOut: The first human base on Mars is called Bowie Base One. There's a DavidBowie song called "Life on Mars".
** It's the wrong song, but both halves of the line ''Planet Earth is blue, and there's nothing I can do'' from "Space Oddity" seem significantly reflected in this episode (not to mention the event of someone dying in space for reasons never known back on Earth).
** When the Doctor changes history, we see [[Film/BackToTheFuture news entries with changing text]].
*** Not to mention the [[Film/BackToTheFuture flaming tire trails]].
** The sound the computer makes when it tracks the crew members is from ''TwoThousandOneASpaceOdyssey''.
** Possibly unintentional, but the horrific alien zombie virus is called [[{{Halo}} the Flood]].
** A member of the crew is infected by the virus when [[Film/TwentyEightDaysLater a drop of the tainted liquid hits their eye.]]
** The door that leads into the comm room where Adelaide contacts The Doctor closes with the [[DoomDoors same sound effect]] as the doors in the video game ''VideoGame/{{Doom}}''.
** The idea of one drop of water contaminating the global water supply may have been borrowed from KurtVonnegut's ''CatsCradle'', in which a similar plot device causes [[spoiler:the world's entire water supply to turn into ice-nine, bringing about a planetary ApocalypseHow that is implied to cause the eventual extinction of all life on earth]].
* SlasherSmile: Briefly adopts one while using Gadget to remote pilot the TARDIS.
* SurvivalMantra: After the Doctor snaps, channels the Master and starts fighting the water: "Not beaten, ''not beaten''".
* TemptingFate: The Doctor when he realises where he is.
--> '''Doctor''': I should go. I really... should go.
--> *Hears a roar over the tannoy*
--> '''Doctor''': Oh, I really should go...
** Later when they are evacuating the base.
--> '''Doctor''': Right, I should leave! ''Finally''! I ''should'' leave! Yuri my old mate, no, no point in me seeing the Ice-field? No point at all! No... *begins to run after her* ADELAIDE!
* ThereCanBeOnlyOne: In the Doctor's "Time Lord Victorious" speech, he says that as the last Time Lord, he is the "winner" and master of the laws of time, [[ScrewTheRulesIMakeThem allowing him to break them]].
* TheyCallMeMisterTibbs: The Captain, upon being called "boss".
* UnresolvedSexualTension: Kind of implied between Adelaide and Ed; see NoodleIncident.
* TheVirus: The Flood.
* WaterSourceTampering: Turned UpToEleven with the aliens ''in'' the water.
* WhatTheHellHero: The Doctor himself is called out on this by Adelaide. Several times.
* WorldOfCardboardSpeech
* TheXOfY
* YouCantFightFate / ScrewDestiny: Played with in pretty much every way possible.
* ZombieInfectee: Averted - the infectee immediately tells the others to leave him behind.