[[quoteright:350:http://static.tvtropes.org/pmwiki/pub/images/slitheen_2851.jpg]]
->'''Rose:''' My mum's here.\\
'''The Doctor:''' Oh, that's just what I need. Don't you dare make this place domestic.\\
'''Mickey:''' You ruined my life, Doctor. They thought she was dead. I was a murder suspect because of you.\\
'''The Doctor:''' You see what I mean? Domestic!

One trip to the past, one trip to the future, and now the Doctor brings Rose home, safe and sound, twelve hours after she left...

But then the Doctor spies a peculiar missing person bulletin on a telephone pole and turns aghast. He rips it down, and discovers the person in the photograph... is ''Rose.'' Meanwhile, Rose runs in to her mum's flat, thinking she hasn't been missed, only to watch Jackie shatter a coffee mug in shock at the return of her daughter and fall apart in her arms. Rose then spots an enormous pile of posters in the flat, all saying Rose has been gone since 2005...

Make that twelve ''months'' after she left. Oops. Jackie's life has been hell, [[{{Deconstruction}} Mickey has been under police investigation for Rose's "murder" and is severely traumatised]], the police question the Doctor on whether his relationship with Rose is sexual, and Rose now has to cope with everyone thinking she went mad and ran off with a random middle-aged northern bloke in a leather jacket.

Jackie goes all MamaBear on the Doctor, Mickey sulks in the background and an enormous spaceship clips Big Ben and crashes into the Thames. The Doctor, hearing that the spaceship's pilot has been taken to Albion Hospital, sneaks off to investigate. But the only strange life form he encounters there is [[Characters/{{Torchwood}} Tosh]], working for Torchwood. [[note]]Also, covering for Owen, who was hung over that day.[[/note]]

The British government is in full crisis mode, here defined as "a bunch of people running around, not sure what to do". Harriet Jones (MP, Flydale North) displays a crackerjack sense of timing as she decides that the middle of an alien invasion is the perfect time to advance her pet project (hospital standards of excellence, in case you're wondering). Everyone fends her off, on the grounds that there's an ''alien invasion'' on, so she sneaks into the Secret Meeting Room and puts her project briefing folder inside the official alien invasion briefcase. Approaching footsteps warn her to hide in a convenient cupboard, so she's the first to discover that the acting heads of the British government have been taken over by aliens! Dun duh DUUUUN!

The Doctor goes back to pick up Rose, freaking out Jackie but acquiring the invaluable help of Mickey -- who's kept himself busy with research in the past year and knows that the Doctor [[Recap/DoctorWhoS7E1SpearheadFromSpace was officially a UNIT employee a few decades back]]. Jackie gets on the phone and reports an alien sighting of a ''specific'' alien, namely the Doctor, which makes the British government go even ''more'' apeshit. UNIT immediately sends their black helicopters after the Doctor and Rose, and pretty soon they're on their way to 10 Downing Street for a conference on aliens. The Doctor is able to join in as the UK's resident alien expert.

Rose isn't allowed in, so Harriet Jones (MP, Flydale North) takes her aside and confides to her about the alien thing. The Doctor comes to roughly the same conclusion a few minutes later, when he realizes that the conference on aliens is an excuse to gather all the most knowledgeable about aliens in one room, and then kill them.

!Tropes
* AccidentalMisnaming: The Doctor insists on calling Mickey "Ricky".
--> "I think I know my own name!"
--> "You ''think'' you know your own name? How stupid are you?"
** Then in "Rise of the Cyberman," it's discovered that Mickey is replaced by the identical looking "Ricky" in the parallel universe.
* AlienNonInterferenceClause: The Doctor decides that if this really is first contact then it's something humans have to work out for themselves. Once he confirms it's a trap, it's back to business as usual.
* AliensOfLondon: TropeNamer.
* ArcWords: A kid spray-paints "BAD WOLF" on the side of the TARDIS. As a BrickJoke, the kid is seen in the next episode scrubbing it off.
* BavarianFireDrill: The Doctor manages to get out of being held at gunpoint by a room full of soldiers by shouting "[[AttackPatternAlpha Defence Plan Delta]]! Come on!" after a scream is heard. He didn't even flash his psychic paper!
* BlatantLies: When Jackie is chewing out the Doctor and Rose at the beginning.
-->'''Jackie Tyler:''' The hours I've sat here, days and weeks and months, all on my own! I thought you were dead! And where were you ''traveling''?! What the hell does that mean, traveling?! That's no sort of answer! ''[turns to the police officer in the room with them]'' You ask her! She won't tell me. That's all she says, "Traveling!"
-->'''Rose Tyler:''' That's what I was doing!
-->'''Jackie Tyler:''' When your passport's still in the drawer! It's just one lie after another!
-->'''Rose Tyler:''' I meant to phone. I really did, I just...I forgot.
-->'''Jackie Tyler:''' What, for a year? You forgot for a year?! And I'm left sitting here! I just don't believe you! Why won't you tell me where you've ''been''?
-->'''The Doctor:''' Actually, it's my fault. I sort of, er, employed Rose as my companion.
-->'''Policeman:''' When you say companion, is this a sexual relationship?
-->'''The Doctor, Rose Tyler:''' ''[look at each other]'' No!
-->'''Jackie Tyler:''' ''[gets in the Doctor's face]'' Then what is it?! Because you, you ''waltz'' in here all charm and smiles, and the next thing I know, she vanishes off the face of the Earth! How old are you then? Forty? Forty five? What, did you find her on the Internet? Did you go online and ''pretend'' you're a doctor?
-->'''The Doctor:''' I am a doctor!
-->'''Jackie Tyler:''' Prove it! Stitch this, mate! ''[strikes him hard across the face with her palm]''
* BoardToDeath: The aliens posing as Joseph Green, Margaret Blaine and Oliver Charles (later General Asquith) conveniently discuss their plan in the room where Harriet Jones ([[RunningGag MP for Flydale North]]) is hiding.
* CatchPhrase: "Harriet Jones, MP for Flydale North".
* ChekhovsGun: The flatulence produced by the Slitheen.
* CrouchingMoronHiddenBadass: General Asquith threatens to remove Joseph Green and his comrades from power after their response to his accusations of doing nothing is to laugh and fart a lot. Then they start unzipping their foreheads.
* {{Deconstruction}}: The Doctor takes a young girl up into space, as usual. She leaves her loved ones behind without saying goodbye, as usual. The TARDIS doesn't listen to the Doctor and vworps to the wrong time, as usual... and suddenly, we get to see what happens when all three of those things combine. Rose's mum is deeply traumatized, Mickey was suspected of murder and the Doctor has to explain to the cops that his relationship with Rose is not sexual.
** However this doubles as a slight CallBack to [[Recap/DoctorWhoS26E4Survival Survival]], where Ace finds her mother had her listed as a missing person and some people thought she had died.
* [[AttackPatternAlpha Defense Plan Delta]]
* FirstContact: The Slitheen make up a "first contact" situation as part of a plan to destroy the planet.
* {{Gasshole}}: The whole Slitheen family, due to how they compress themselves to fit into their meat suits.
* GenreSavvy: What is London's emergency protocol for alien activity? ''Find The Doctor''
* [[InvisiblePresident Invisible Prime Minister]]: The episode was broadcast close to the General Election -- when the Doctor asks Rose who the PM is, she points out that she missed a year. When they find the PM's corpse, we never see his face in detail[[note]]WordOfGod states that the actor playing the PM was chosen because of his resemblance to Tony Blair, but his face is obscured because it turned out he didn't look that much like Blair after all[[/note]].
* MixAndMatchCritters: The Doctor compares the humanoid pig "alien" to P.T. Barnum's monkey/fish "mermaid".
* MonumentalDamage: An invoked trope on the Slitheen's part. They deliberately crashed the ship into Big Ben to draw attention and make sure everyone saw it.
* PigMan: The pilot of the crashed ship actually an Earth pig altered to look like an alien.
* PuppeteerParasite: The Slitheen wear skinsuits adapted from the bodies of their victims.
* RetCon: Naoko Mori's character actually being Tosh. It fits rather perfectly, and ''Series/{{Torchwood}}'' was able to effortlessly retcon her from "random girl who happened to appear in ''Series/DoctorWho''" to "Tosh covering for Owen that day".
* TheSlowPath: Everyone connected to Rose. Mickey is thrown when she explains it's only been a few days for her.
* StealthHiBye: The Doctor pulls one on Dr Sato at Albion Hospital.
* [[StuffedInTheFridge Stuffed into the Cupboard]]: The Prime Minister.
* TakeMeToYourLeader: The Doctor is rather excited about being taken to 10 Downing Street.
* ToiletHumour: The Slitheen and the entire matter with the gas exchange.
* TragicMonster: The poor little Pig Alien. Just a regular pig turned into an abomination against science, and crashed into the Thames. Poor thing gets shot dead by a spooked soldier.
-->'''Doctor:''' He was ''scared!''
* TrailersAlwaysSpoil: The "Next Time" trailer for the following episode began ''immediately'' after the cliffhanger, and showed that all but one of the characters with lines (including minor ones who the viewers might have thought were going to die) would survive. Needless to say, many fans (and even casual viewers) were pissed off at the first ''Doctor Who'' cliffhanger in sixteen years being utterly ruined, and future episodes of the series would have the "Next Time" trailer moved to being after the end credits, giving viewers enough time to turn the channel.
** To a lesser extent, the trailer for this episode on "The Unquiet Dead", which spoils which characters are actually the Slitheen. However, this episode doesn't bother keeping the identities of the Slitheen secret for very long, so it's much less of an issue than the aforementioned instance.
* {{Troll}}: Russell T Davies deliberately inserted a line of dialogue for Rose where she said to the Doctor, "You're so gay!" to set off a heated discussion about homosexuality within fan circles. For the record, Davies himself is also a homosexual.
* UnexpectedSuccessor: Part of the Slitheen's plan.
* {{Whitehall}}: Number 10, Downing Street is the setting of most of this episode and the next.
* TheXOfY
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