The Waters of Mars ( TV story ) The Waters of Mars was the first " Doctor Who " special not tied to a particular holiday . Mostly a character piece , it showed the extremes to which the Doctor would go when unregulated by either other Time Lord s or companion s , specifically by trying to change a fixed point in time . It continued the " He will knock four times " story arc begun in the previous episode . It won a 2010 Hugo Award for writers Russell T Davies and Phil Ford . After years of stability at the producer ' s office , " The Waters of Mars " was the fourth episode in a row to be produced by a different person . Just prior to his regeneration a significant change in the Tenth Doctor ' s character was presented , showing a much darker and callous side . Up to this point he had viewed himself as a survivor of the Time War , but now he started to believe that he was the " Time Lord Victorious " and that the Laws of Time were his to command , allowing him to break them because there were no other Time Lords around to stop him . After saving Adelaide Brooke even though he knew her death was fixed , he realised that he had gone too far and that he should not influence history and the future on such a large scale . Adelaide ' s flashback also indicates that the Daleks are aware of people and events important to the universe ' s history . The consequences of altering such important events is displayed in " The Wedding of River Song " , when the Silence create an event that appears to be the Eleventh Doctor ' s assassination ; if the event is prevented , it will stop time and cause all of history to happen at once at the epicenter . In time , the effects will spread to the rest of reality and the universe would simply collapse . This is the first time since 1980 ' s " Logopolis " , that the Cloister Bells have rang to signal to the Doctor that he will regenerate soon . However , unlike the previous time , where the Fourth Doctor was willing to wait for his time to come , the Tenth Doctor was greatly fearful of having to regenerate . Unknown to the audience at this time , the Doctor had only one regeneration left ; he had aborted one in " Journey ' s End " , and kept one secretly buried in his memory . While " The End of Time " is the next aired episode featuring the Tenth Doctor , the events of " The Day of the Doctor " follow " The Waters of Mars " in the Tenth Doctor ' s timeline . Synopsis . Mars , 2059 , Bowie Base One . Last recorded message : " Don ' t drink the water . Don ' t even touch it . Not one drop . " Plot . The TARDIS arrives on Mars and the Tenth Doctor steps out in his spacesuit from Sanctuary Base 6 , seemingly just to relax and enjoy the landscape . Stumbling across a base inhabited by a team from Earth , he is detained by a remote - controlled robot called " Gadget " and taken inside . The base commander , Adelaide Brooke , holds the Doctor at gunpoint , demanding to know his name , rank and intentions ; he responds " the Doctor ; doctor ; fun . " The crew wonder if he ' s from a rival space agency , to which the Doctor decides to agree to ; he then asks who they are . Adelaide scoffs at him saying that everyone on Earth should know who they are as they are the first colonists on Mars . The Doctor realises that the date is 21 November 2059 , and this is Bowie Base One . History has it that on this date , the base was destroyed in a mysterious explosion and Brooke and her crew were all killed . Unwilling to break the laws of time and interfere with a " fixed point " in history , the Doctor states that he is sorry with all his hearts , but he needs to leave . However , a crisis is developing : a crew member , Andy Stone , has been infected by a mysterious life form which takes over his body and causes him to gush copious amounts of water . Maggie Cain , another crew member , screams as Andy growls and attacks her , leaving her unconscious in the biodome corridor . After second - in - command , Ed Gold , attempts to establish contact with Andy and Maggie over the comlink and they hear Andy ' s guttural snarls over the comlink , Adelaide confiscates the Doctor ' s spacesuit , thinking he may be responsible for the infection in some way , and orders him to come with her and physician , Tarak Ital , MD , to investigate . As the Doctor , Adelaide and Tarak walk down the corridor with Gadget , operated by Junior Technician Roman Groom from the central dome , the Doctor finds it annoying that the robot repeats its name . The Doctor asks the famous Adelaide Brooke if the Bowie Base One mission was worth everything she sacrificed , to which the Captain replied that Earth was reaching the point of uninhabitability with all the smog and pollution , all of which pushed humanity to the brink of extinction , and that to walk on another planet without any smoke but just infinite sky . . . yes , it ' s worth it . The Doctor is greatly impressed , and tells Adelaide that she was the woman with starlight in her soul . Adelaide says nothing , but her expression is thoughtful . As they walk down the corridor , Adelaide ' s torch picks out Maggie ' s unconscious form , and they race to her . She is still alive and breathing , but has a nasty gash on her head . Tarak calls Nurse Yuri Kerenski over the comlink , who arrives with a medi - pack for Maggie and a stretcher . Ed also arrives , after realising that only one other person was in the biodome — officer Andrew Stone . Ed tells Maggie that the only way this couldn ' t have been an accident was that Andy has gone berserk . Adelaide dismisses him using rank and citing security protocol . Meanwhile , Senior Technician Steffi Ehrlich checks the growling noise on the diagnostics unit of the computer , and is shocked to discover that the growling was the voice of Andy Stone . She calls Adelaide on the comlink to warn her that it seems Andy has gone wild . Adelaide , Tarak and the Doctor step into the dormant biodome , and , using his sonic screwdriver , the Doctor restores the lights , all of which had been shorted out by the infected Andy . Tarak goes to the left to check the biodome airlock doors , while Adelaide and the Doctor go to the right . Maggie awakens as they walk down the biodome , unwittingly carrying the mysterious virus which is hiding in her body , but she has amnesia of the previous occurrences . Slightly groggy , she tries to get Yuri to open the door for her to come out , but Yuri refuses , saying a little rest won ' t hurt . As he turns his back , however , Maggie ' s features crease into a disapproving frown , indicating that she is not herself anymore . . . Tarak is the first to find Andy , who swings round onto him and infects him with the virus by pouring water over his head , causing Tarak to acquire the same zombie - like characteristics that Andy has . At that point , in a conversation with Yuri , Maggie ' s virus finally becomes active . The organism occupying her body reveals its desire to reach Earth , a planet rich in water . Yuri is first alerted to her transformation when she speaks in a deep voice distorted by the internal fission , " We should like that world " , while gazing at planet Earth on a monitor , and Yuri , stammering in horror , briefly describes what has happened to their comrade : the skin around her mouth has become horrifically cracked and broken , her teeth have blackened and she is emitting water in an overwhelming torrent from her mouth , as if she is drowning . Adelaide , realising the biodome is unsafe , tries and fails to establish contact with Tarak over the comlink , and then she and the Doctor run back through the dome in time to see Tarak transform . While Adelaide points her gun at her infected crew member , the Doctor tries to encourage Andy to take his dripping hand away from Tarak ' s head . Amazingly , Andy seems to obey , and yanks his hand away from Tarak , who collapses as his mutation is completed . The Doctor then acts friendly and introduces himself to the infected man , but then Tarak flicks his head up and turns to face them , and they are horrified to see that Tarak now looks just like Andy — the skin of his mouth has cracked , his eyes are a dead , white - blue , his teeth have gone black and copious water pours from his mouth . The Doctor , realising they have to get away , runs with Adelaide hot on his heels , but then Andy and Tarak run after them back through the dome to the door , whose seals are set at maximum , just as Andy fires a thick stream of viral water from his hand onto the door . Not a single drop gets inside , but Andy then steps closer to the door and slams himself against it . Ed reaches the medical dome to see Maggie for himself . He is shocked by her appearance , and his face shows his fear . Steffi , geologist Mia Bennett and Roman look through the medical dome camera at Maggie , and Steffi wonders what she has become . She calls Adelaide over the comlink , begging her to come back , but Adelaide orders Ed to make sure that Maggie is contained . Ed confirms it , then Adelaide orders all the water supplies to be closed down , and also orders the others : " Don ' t drink the water , don ' t even touch it , not one drop " . The Doctor examines Andy , who looks at him with his dead white eyes , and suddenly grins . The Doctor fails to get a response from the zombie or his friend standing behind him . Andy then starts examining the door , and the Doctor realises that humans are 60 % water , so they are the perfect host for something like a mutating water virus . The Doctor says he has to go , and that he can ' t stay to see what happens , leaving Adelaide confused . Suddenly , Andy slams his whole body against the door , making both the Doctor and Adelaide jump . Andy growls at Tarak , who then attacks the door by firing water from his mouth into the side , fusing the systems and causing the tortured door to open . The Doctor and Adelaide escape and start running down the corridor back to the central dome , but Andy and Tarak then break out of the biodome doors and race after them . Realising that the infected men can run faster than them , the Doctor sonics Gadget , making him able to move considerably faster , and he and Adelaide hitch a ride on the robot , which causes agony to Roman Groom , the robot ' s operator . The Doctor notes the crew should have had collapsible bikes brought along . Andy and Tarak , still infected , chase the Doctor , Adelaide and Gadget back to the central dome , but are unable to pursue them any further due to the hardinger seal s in the central dome airlocks and are contained in the base ' s " bio - sphere " section while Maggie is secured in the medical wing . The Doctor , however , is worried about the doors and whether they can protect them from creatures with such power , making a chilling statement , " Water is patient , Adelaide , water just waits . It wears down the clifftops , the mountains , the whole of the world . Water always wins ! " In the medical dome , the Doctor and Adelaide meet the infected Maggie , who just stares at them all , but she suddenly takes an interest in the Doctor when he speaks ancient North Martian to her , Maggie appearing to understand it . The Doctor realises that , looking at Maggie ' s blackened mouth and cracked skin , that whatever the infection is , it doesn ' t just live as water , it can produce immense amounts of it . The crew plan to evacuate in an escape shuttle , and the Doctor grimly tells the news to Adelaide that they could be carrying the infection , as they discovered , from Maggie ' s transformation , that the infection could hide in a human and mutate it at any moment . As the Doctor and Adelaide go to inspect the glacier from which the virus came from , Maggie breaks out of confinement by seeping water into the door and alerts Andy and Tarak in the biodome corridor to the humans ' plans by emitting a terrifying alien scream that is heard by the two men over a hundred metres away . The infected men slowly lower their heads and then look towards the medical dome from which the scream is coming from , then they slowly walk away . In the dome containing the glacier , the Doctor hypothesises that the virus may have been preserved and imprisoned in the glacier by the Ice Warrior s to prevent its spread . However , before they can get to work , Adelaide queries the Doctor on how he knows so much about them . Reluctantly , the Doctor comments that she may have a story to tell , and Adelaide agrees . She says that when she was 10 years old , the sky had changed , as it was the moment when the Earth was snatched by the Daleks , and Adelaide says that she saw a Dalek float down to her window , and it saw her and just stared at her , then flew away . Adelaide says that she knew , someday , she would follow it into the stars . The Doctor tells Adelaide that by doing so , she has created history and reveals some information ; Adelaide ' s infant granddaughter Susie Fontana Brooke will grow up and , inspired by her grandmother , become the pilot of Earth ' s first lightspeed ship . This will pave the way for generations of her descendations to explore the galaxy , with one even falling in love with an alien prince and creating a whole new species . Adelaide , amazed at what a lasting legacy her and her family will have on the galaxy , asks the Doctor why he ' s telling her all this . The Doctor sadly replies that he ' s telling her as a consolation . The Doctor and Adelaide work out , through a last message from Andy , that the water was fine to drink until the filter broke and the virus could get into the water supplies . Since the water won ' t yet have been drunk by the rest of the crew , they are free to leave . The crew plan to evacuate in an escape shuttle , and the Doctor breaks the news to Adelaide that she must die today , on Mars , if events are to unfold as they should . Adelaide begs him to help but the Doctor insists he cannot interfere as her death is a fixed point in time , something even the Dalek knew which is why it didn ' t kill her as a child . Adelaide allows him to leave , saying two last words : " Damn you " . However , as the crew prepare to leave , Andy and Tarak climb the maintenance shafts in the main dome , walk to the centre of the roof of the control centre , fall to their knees and exude more water from their hands and mouths through the girders in the roof . The water quickly pours into the room and claims a distraught Steffi Ehrlich as she watches a tape left by her two daughters . Shortly afterward , Roman is infected when a single drop of viral water falls on his cheek . However , he warns the others to run just before he changes . Mia screams and sobs as he is infected , but Yuri restrains her , and so they all make for the shuttle . As Ed prepares the shuttle for take - off , Maggie infiltrates the shuttle and blasts water up the shaft into the pilot room , which cascades over Ed ' s arm , infecting him with the virus . However , just as the infection consumes him , and his eyes turn white - blue , Ed bids Adelaide , Yuri and Mia a final farewell , " See you later " , and triggers the shuttle ' s self - destruct system , which traps the Flood on Mars but leaves the rest of the crew stranded with no means of escape . The Doctor narrowly avoids being caught in the blast , but nevertheless can hear the cries of the doomed and their desperation as escape seems hopeless . Tortured by their suffering , he thinks about how the Time Lords used to enforce the laws of time , but they are all dead and gone now . He is the last Time Lord ; he can make his own rules . With fierce determination on his face , he returns to the base to save the crew . Finding the base falling apart , the Doctor rallies Adelaide , Mia and Yuri , and tries to assess the situation . Adelaide insists that the Flood cannot be stopped and the Doctor should save himself , but the Doctor tells of the prophecy that four knocks with precede his death and states , " It doesn ' t mean right here , right now , ' cause I don ' t hear anyone knocking , do you ? ! " . In response , the infected Andy slams his fist against the door three times ; the Doctor shouts back , " Three knocks is all you ' re getting ! " and electrifies the door , causing Andy to conduct the electricity , scream with pain , and let go of the door . The Doctor realises that , coming from Mars , the Flood creatures would be very sensitive to heat . He reasons that if heat worked against the Ice Warriors , it would work against the Flood . He plans to activate the environment controls and boil them . Adelaide reminds him of his assertion that they must die to ensure history unfolds correctly , but the Doctor replies that as the last of the Time Lords , " The laws of time are mine , and they will obey me ! " Suddenly , an explosion rocks the base , destroying its environmental controls . The Doctor states he will reactivate them from outside , only to find his spacesuit damaged as the glass in the helmet has cracked . Refusing to admit defeat , he plans to get a spacesuit from the storage section of Bowie Base , only to find the entire section flooded . At the same time , Maggie heads to the glacier and lets out a deafening shriek that begins to crack the very ice . As the glacier cracks under Maggie ' s screams , the base ' s stability begins to collapse ; sensing that history will follow its inevitable course , Adelaide activates Action 5 — a nuclear device placed at the heart of the base . It will destroy the Flood , but also kill everyone else , infected or not . The Doctor , realising they have one chance , uses Gadget to roll across the Mars landscape and bring the TARDIS to the base . As time runs out , Maggie continues to wail at the glacier , causing even more ice to crack , and the other infected personnel , Andy , Tarak , Roman and Steffi begin to scream as well , adding their efforts to the Flood ' s release . Just as the Flood begins to escape the glacier , the TARDIS materialises in the control room , and the survivors get inside . The nuclear device explodes , destroying the base and wiping out all the Flood creatures , the explosion unnoticeable from Mars ' atmosphere . The TARDIS materialises outside Adelaide ' s house on Earth . Mia and Yuri are shocked by their experiences on Mars and by the Doctor ' s power , with Mia running away in fear . Yuri promises to take care of her and also departs . Adelaide asks what happens now in regards to her granddaughter ' s future , and the Doctor tells Adelaide that she can still inspire Susie but now can do it face - to - face . Some of the details will be different , but history will still follow its proper course . Adelaide , beginning to realise the full implications of her survival and how it could change her granddaughter ' s future and that of the whole human race , warns the Doctor that he has no way of knowing that and tells him she should have been left on Mars . The Doctor argues that the rules of the Time Lords were only valid while their civilisation existed , and that since he is the last of his race he has total authority over time . He states that he no longer considers himself to have survived the Time War , but to have won it and proudly declares himself the " Time Lord Victorious " and remarks that with this power he will now be able to save influential figures such as Adelaide as well as " little people " : the likes of Yuri and Mia . Horrified by the Doctor ' s newfound arrogance , Adelaide says : " Who decides how important they are ! ? I don ' t care who you are , the Time Lord Victorious is " wrong " ! " . After that , an adamant Adelaide returns home . The Doctor begins to walk away from her door , thinking all is well . He is grievously wrong . The windows of her house erupt with blue light as a single laser blast rings out . Adelaide has committed suicide , reverting the changes that the Doctor has made to the timeline . The Doctor feels the course of history being re - written . The people of Earth are made aware of the horrific events that occurred on Bowie Base One when Yuri and Mia eventually come forward . Captain Adelaide Brooke is now recorded as having died on Earth , with the circumstances of her suicide never found ; however , Adelaide ' s granddaughter will still travel into space and pave the way for her future generations , inspired by Mia and Yuri ' s stories of her grandmother ' s heroism . Only now understanding the full impact of his actions , the Doctor is overcome with horror , and realises that there will be a price to pay for his interference . A vision of Ood Sigma appears in the street , prompting the Doctor to ask him whether he has finally gone too far — whether the time has come for him to die . The fear in his voice is incredibly potent . Unresponsive , Sigma vanishes , and the Doctor staggers back into the TARDIS . The Doctor is greeted by the ominous sound of the Cloister Bell warning the Doctor that the time for him to regenerate is near . Solemnly tossing off his coat , the Doctor contemplates this . With a defiant " No ! " , he begins to work the machine ' s controls in a desperate plight to delay his impending death as long as he possibly can . Home video releases . The four specials along with " The Next Doctor " were released in North America on both DVD and Blu - Ray in a box set on 2nd February 2010 . This DVD would then be released in the UK in 2014 , with the same content intact . " The Waters of Mars " was released with " The End of Time " in a ' Winter Specials ' DVD and Blu - Ray Box Set .