Written by Russell T. Davies.
A medical student called Martha Jones heads off to a normal day at work, and a strange man comes up to her in the street, says "Like so!", and takes his tie off. Martha, only mildly perplexed, continues to the hospital, where she encounters the same man, calling himself "John Smith". He's been in the hospital all day and has no idea what she's talking about. To top it off, the mysterious John Smith has two hearts. Then it starts to rain upwards, and the hospital ends up on the Moon. The Doctor decides that Martha, being unperplexed by his two hearts (unlike some companions) and not flipping out over being on the Moon, is exactly the sort of person he could use for help, so he enlists her in the task of saving the hospital.
Meanwhile, a herd of rhino-alien-police (Judoon) enter the hospital and begin to methodically search it for alien life, so the Doctor needs to find the malicious alien and keep himself out of rhino hands, all before the hospital's supply of oxygen runs out.
The alien in question is an old granny, a humanoid plasmavore, who is wanted for murder. She drains the head of the hospital, then fools a Judoon scan because the blood makes her read as human. (And, to distract the rhinos for a while, the Doctor puts some of his own alien bio-bits on Martha by snogging her. No complaints from Martha.) Anyway, Granny has devised a plan to save herself that will kill the human population (the half facing the Moon, anyway). She imparts this plan in detail to mild-mannered "John Smith" and then drinks his blood.
Martha finds the plasmavore just as she drains the Doctor dry, which, unbeknownst to her, renders her decidedly alien on any bio-scan. The Rhinos kill the plasmavore and Martha revives the Doctor, just in time for him to reverse the doomsday MRI scanner and save humanity. In return for saving his life, the Doctor offers Martha a quick tour of the galaxy in his TARDIS. She refuses at first, but then, in response to her question of how he would prove that the TARDIS can travel through time, he steps into the TARDIS, disappears, and reappears with his tie off. See first sentence.
The Doctor promises her one little trip, just for fun, and they awkwardly agree that she's not there to replace Rose. Also, Martha's only attracted to humans. With those negotiations over with, they're on their way.
- All Gravity Is the Same: We're given no explanation why the hospital has the same gravity after being brought to the moon.
- Alliterative Name: The plasmavore chose an alliterative alias: Florence Finnegan.
- Almost Out of Oxygen: The force-field keeps the air in, but it starts running out quickly. Thankfully, the Judoon aren't completely merciless and teleport the hospital back once they're done.
- Apocalypse How: Had the Plasmavore won, her Evil Plan would've caused a Class 1 in terms of humanity, likely a Class 4 in terms of the Earth's biosphere. Her modifications to the MRI would've sent out a World-Wrecking Wave from the moon which would've fried every last brain stem within a range that included the side of the Earth facing the moon at the time (and only that side).
- Arbitrary Scepticism: The first time Martha meets the Doctor, she hears that he has two heartbeats and instantly accepts that the hospital has been transported to the Moon and that the Judoon are aliens, but refuses to believe the Doctor is an alien until a Judoon scanner confirms it.
- Arc Words: There's "Vote Saxon" signs in the alley at the end, and Mr. Saxon gets name-dropped.
- Assimilation Backfire: Finnegan drinks human blood so the Judoon will think she's a human when bio-scanned. The Doctor tricks her into drinking his blood, thus making her look like an alien through the bio-scanner, albeit different from what she actually is.
- Beethoven Was an Alien Spy: The Doctor used to have a laser spanner, but it was stolen by Emmeline Pankhurst.
- Big Red Button: Martha is told to activate a radioactive machine to take down one of the slabs. Not knowing how to do that she tries reading the operator's manual, but time being of the essence, eventually gives up and plums for the big yellow button. It works.
- Bigger on the Inside: Can't be an official Companion if you don't mention it. Complete with the Doctor mockingly mouthing along when Martha says it. (Which was not in the script.)
- Blatant Lies:
- Blind Shoulder Toss: The Doctor is lamenting his broken sonic screwdriver when he realizes Martha is trying to tell him something, and simply tosses it behind him.
- Blue-and-Orange Morality: The Judoon have a pretty strange concept of justice. They don't hesitate to pronounce and carry out a death sentence on a man for breaking a vase over a soldier's head, even though the soldier was fully armored and completely unharmed, and when the hospital appears about to explode they depart without any effort to stop it. But when their leader takes an unusually long time verifying that Martha is human, he insists on giving her "compensation" in the form of a piece of paper in an alien language (it's never clear what it is), and when the hospital doesn't blow up, they send it back to Earth.
- This may be more Lawful Stupid, since the whole reason they took the hospital in the first place was to comply with jurisdiction rules.
- Brick Joke:
- This brick falls in reverse. At the very beginning of the episode, Martha Jones first meets the Doctor when he steps in front of her in a crowd of people, says "Like so", takes his tie off and waves it in her face, and walks off. When she arrives at the hospital, she sees the Doctor being examined. She calls him out on his stunt, but the Doctor denies his involvement, as he has been in bed the entire time. The rest of the episode consists of the hospital being sent to the Moon, avoiding an army of rhino-men and fighting a vampire. When that's finally over, the Doctor explains to Martha who, and what, he is, and that the police box is a time machine. When she doesn't believe him, he says he'll prove it to her, and gets inside the TARDIS and it disappears... only to reappear seconds later with his tie off.
- The Doctor squeeing over the hospital having "a little shop!"
- Bridal Carry: The Doctor carries an unconscious Martha with him as he goes to watch the hospital being teleported home.
- Bystander Syndrome: After the Judoon execute the Plasmavore, they claim their jurisdiction is over and leave without dealing with the overloading MRI, much to Martha's ire.
- Call-Back: Martha's "welcome aboard" scene is almost identical to that of Peri in "Planet of Fire". In both cases, the Doctor and the companion fall on the console before the Doctor makes his welcome.
- Casting Gag: Eighteen years previously, Anne Reid played a victim of vampiric humans from the distant future, and now plays an alien with similar dietary preferences.
- Chekhov's Gunman: Florence Finnegan, the first patient Martha and her fellow students are shown visiting. After the hospital is taken to the Moon, she's seen asking various people for help while aliens are causing chaos, making the audience think she's just a confused and clumsy old lady. Then it's revealed that she's actually the blood-sucking villain the aliens are looking for.
- Comically Missing the Point: The Doctor has just absorbed a lethal-to-humans dose of radiation and is trying to expel it via his foot into his shoe.The Doctor: Ow, ow, itchy, itchy, itchy... [shakes foot wildly, hopping around on one foot, before pulling his shoe off and binning it triumphantly]
Martha: You're completely mad.
The Doctor: You're right. I look daft with one shoe. [bins his other shoe] Barefoot on the Moon!
- Computer Equals Monitor: When the computer's database is erased, the Doctor looks for a backup by checking the back of the monitor.
- Continuity Nod: The Battle of Canary Wharf is mentioned. Martha's cousin Adeola never came home that day. Martha can also accept the idea of aliens because of past incidents like the alien spaceship that crashed into Big Ben.
- CPR: Clean, Pretty, Reliable: Apparently CPR will fix clinical death brought on by blood loss in non-humans. Considering how little we know about Time Lord biology, this could be true.
- Death Is Cheap: The Doctor is drained of a significant amount of blood and somehow revived by CPR.
- Defiant to the End: Once she's finally cornered, the Plasmavore gleefully admits her crimes.Judoon: You confess?Plasmavore: Confess?! I'm proud of it! [she activates the MRI] Enjoy your victory, Judoon, 'cause you're gonna burn with me! BURN IN HELL!
- Dies Wide Open: Dr. Stoker, after the Plasmavore drains his blood. Martha closes his eyes for him.
- Disproportionate Retribution:
- As Oliver Morgenstern is telling terrified patients to cooperate with the Judoon as they scan everyone looking for the plasmavore, one patient grabs a vase and smashes it over another Judoon.Judoon Captain: Witness: a crime. Charge: physical assault. Plea: Guilty. Sentence: execution. [vaporises the man on the spot]
Oliver Morgenstern: You didn't have to do that.
Judoon Captain: Justice is swift.
- The Doctor is in a bit of a rush to get to the Plasmavore before the Judoon find her because he knows that the Judoon will execute everyone in the hospital for harbouring a fugitive if they find her first.
- As Oliver Morgenstern is telling terrified patients to cooperate with the Judoon as they scan everyone looking for the plasmavore, one patient grabs a vase and smashes it over another Judoon.
- Does Not Like Shoes: The Doctor is barefoot for most of this episode. Both justified and lampshaded by the fact that he exposed himself to radiation, and then expelled it to his left shoe, so naturally he had to take his shoe off, but Martha, naturally, thought him taking all the radiation was madness. He, however, takes that to mean that he will look "daft" with one shoe, so he pulls the right one off too, then refers to himself (complete with a close-up of a sexy pair) as "barefoot on the Moon". Also, later in the episode, he tries to hide his true identity, and justify why he is barefoot by saying he came into the hospital for his bunions.
- Eat Me: The Doctor goads the Plasmavore into drinking his blood to expose her.
- Establishing Character Moment: Martha is introduced on her way to work taking various phonecalls from members of her family, calmly mediating everyone's issues for her brother's upcoming birthday party.
- Evil Gloating: The Plasmavore doesn't exactly confess, because confessing implies guilt. She's proud of sucking a little girl's blood.
- Fainting: Martha uses CPR to revive the Doctor, who has fainted dead away after having a life-threatening amount of blood drained by a plasmavore.
- Fake-Out Make-Out: A time-delayed version. The Doctor kisses Martha before running away, so that some of his non-human DNA will register on her, and the aliens hunting for it will be held up double-checking that Martha is human, buying him some time.
- Foreshadowing: The Plasmavore in this episode is masking her biological species to evade detection. Later in the same season, both the Doctor (in "Human Nature") and the Master (in "Utopia") also do this.
- Freak Out: Nearly everyone in the hospital on seeing they're on the Moon.
- Genre Savvy: Martha seems to find the sci-fi elements of the story a lot easier to accept than Rose or Donna did, partly because she's aware of the various current-day stories from the first two series. (Also, the audience was a lot more comfortable with it all by this point, so there wasn't as much need for the Audience Surrogate to be mystified.)
- Glowing Eyes of Doom: Actually justified the villain's eyes are glowing because they're reflecting the discharges coming from the MRI scanner.
- God Test: The reason the Doctor takes his tie off in front of Martha at the beginning is that, at the end of the episode, she asks him to prove he's a time traveller.
- Have We Met Yet?: Martha recognizes the Doctor in the hospital, but he has no idea what she's referring to until the end of the episode when he does his "cheap trick".
- Hell-Bent for Leather:
- Parodied with the Slabs, androids composed entirely of leather, because of someone's fetish.
- Played more straight with the Judoon, who are very dangerous.
- Hoist by His Own Petard: The Plasmavore has been hiding from Judoon scanners by feeding on humans and incorporating their DNA. Then the Doctor lets her feed on him, and as we (especially those Judoon scanners) all know, he's not human, either.
- Hollywood Midlife Crisis: Clive Jones seems to be in the middle of one. He's about to turn 50, recently-divorced and sporting a brand new car and a 21-year-old Caucasian girlfriend the script compares to a Big Brother eviction night.
- Human Aliens: Florence appears to be one, but that may just be a result of her disguise method. The Doctor, of course, is one, and this is used as a plot point when Florence is tricked into using his blood for her disguise.
- Idiot Ball: The Judoon, about to go on a patient-by-patient search of the hospital, wipe the patient records. The Doctor does point out they're "thick".
- Impostor-Exposing Test: The Judoon have scanners which can distinguish humans from non-humans, which they try to use to find a plasmavore criminal hiding in a hospital. The plasmavore is able to change her physiology by drinking blood, and tries to use that to beat the test; however, the Doctor tricks her into feeding on him. Since he's an alien, the scanners identify the plasmavore as non-human and kill her.
- Improbable Weapon User:
- Florence Finnigan's method of sucking blood is to use a bendy straw!
- The Doctor kills a Slab with an X-ray machine by increasing the radiation output to fatal levels.
- Florence Finnigan uses an MRI machine which will fry the half of the Earth facing the Moon.
- It Doesn't Mean Anything: The Doctor assures Martha her upcoming smooch is entirely plot-justified. "It means nothing, honestly nothing." All she can say afterwards is "That was nothing?"
- Judge, Jury, and Executioner: The Judoon do this role when one guy tries assaulting one of them with a vase; "Justice is swift."
- Jumped at the Call: Martha catches the Doctor's interest by being the first to figure out the air's being kept in somehow, and being willing to test this theory by stepping out onto the balcony.The Doctor: Fancy going out?
The Doctor: We might die.
Martha: We might not.
- Just Between You and Me: The plasmavore spills her plan to the Doctor because she thinks he's just a hapless human who can't do anything about it.
- Karma Houdini: Sure, the Judoon were polite enough to send the hospital back to Earth when they were done with it, and give Martha "compensation", but they murdered a man acting in perceived self-defence and nearly killed everyone else from oxygen starvation... and if the Doctor hadn't deactivated the MRI, it would have flash-fried everyone (well, half of everyone anyway) on Earth.
- Large Ham: "BAREFOOT ON THE MOON-A!"
- Left for Dead: The Doctor, by a bloodsucking alien after she drained his blood. She was unaware that the Doctor possesses a dual vascular system, so in fact she'd only gotten half his blood, leaving him weakened but ready to pop up and save the day.
- Loophole Abuse: The Judoon have no jurisdiction on Earth... so they transport the hospital to the Moon instead.
- Losing a Shoe in the Struggle: The Doctor, after being attacked by the Slab and killing it with radiation, dismisses Martha's worries about his life by saying he's used to it. He then expels the radiation into his left shoe, which makes his foot itch, prompting him to bin the shoe and sock. Martha says, "You're completely mad", and he agrees, saying he'd "look daft with one shoe". So he bins his right shoe and sock before proclaiming himself "Barefoot on the Moon!", with a Fanservice close-up of his feet.
- Meaningful Echo: Martha Jones is exuding so much calm confidence that she promises the Doctor that she will get him home. These are usually the Doctor's words; he looks slightly non-plussed.Martha: I promise you, Mr. Smith, we will find a way out.
- Meaningful Name:
- Mid-Life Crisis Car: Rusty's script describes Clive's red sports car as "very much midlife crisis".
- Mistaken for Quake: After the hospital is transported, Martha wonders if it was an earthquake.
- Motor Mouth: The Doctor plays this to the hilt when he's trying to come off as a normal human to the plasmavore."Have you seen?! There are these things, these great big space rhino things, I mean, rhinos from space, and we're on the Moon! Big space rhinos, with guns! ON THE MOON! And I only came in for my bunions! Look, they're all fixed now, perfectly good treatment, the nurses were lovely, I said to my wife, I said, I recommend this place to anyone. But then we end up on the Moon! And... did I mention the rhinos?"
- Mr. Smith: The Doctor reuses his preferred alias.
- Mundane Utility: "Crossing into established time streams is strictly forbidden. Except for cheap tricks."
- Noodle Incident:The Doctor: It's a screwdriver and it's... sonic.
Martha: What else have you got? Laser spanner?
The Doctor: I did, but it was stolen by Emmeline Pankhurst, cheeky woman.
- Not a Date:The Doctor: Just one trip to say thanks. You get one trip, then back home. I'd rather be on my own.
Martha: You're the one that kissed me.
The Doctor: That was a genetic transfer!
Martha: And if you will wear a tight suit.
The Doctor: Now, don't!
Martha: And then travel all the way across the universe just to ask me on a date.
The Doctor: Stop it.
Martha: For the record? I'm not remotely interested. I only go for humans.
- Not Using the "Z" Word: The episode features a vampiric creature not named as such. Admittedly, they differ from vampires in some significant ways.
- Obfuscating Stupidity: The Doctor pretends to be a dim-witted human patient dazzled by the alien presence in the hospital in order to dupe the plasmavore into revealing her entire plan.
- Ooh, Me Accent's Slipping: The writers intentionally had some fun with this. The syllable "-oon" is particularly hard for David Tennant to say without sounding Scottish, so they gave him the line "Judoon platoon upon the Moon".
- Organic Technology: Florence uses drone slaves made of solid leather.
- Our Vampires Are Different: The blood-sucking plasmavore is impervious to sunlight, looks completely human, shows up on scanners as whatever species it most recently drank from, and drinks blood from human necks with a plastic bendy straw.
- Personal Raincloud: Referenced the cloud over the hospital, just before the teleport, is compared to one by Tish, like something straight out of the cartoons.
- Pietà Plagiarism: The scene where the Doctor carries Martha after she passes out from the lack of oxygen could be seen this way, especially since there was no particular reason she couldn't have stayed where she was besides drama.
- Police Are Useless: The Judoon find and kill Florence right around the same time they discover she has turned an MRI machine into a weapon that will ravage half of the Earth. They state that the Earth is not within their jurisdiction (which is why they took the whole hospital to the Moon in the first place), and announce their withdrawal. To make things worse, they don't seem to have known the MRI was disabled before returning the hospital to Earth, which would have in fact made the damage caused by it even worse.
- To be fair, the Doctor had said earlier that the Judoon are not so much "police officers" as they are "intergalactic mercenaries for hire".
- Post-Kiss Catatonia: Martha is stunned when the Doctor gives her a kiss but purely so he can leave some of his DNA on her lips to fool the Judoon.
- Preemptive Apology: The Doctor apologises to Martha before the "genetic transfer", though she doesn't have time to be confused about the apology.
- Recycled IN SPACE!: The Tenth Doctor plays with this trope:The Doctor: Have you seen?! There are these things, these great big space rhino things, I mean, rhinos from space, and we're on the Moon! Big space rhinos, with guns! ON THE MOON!
- Retirony: Dr. Stoker says he was planning to go on for two more years and then retire to Florida. Then he cements his fate with a version of the Fatal Family Photo, saying that he has a daughter still attending university.
- Rhymes on a Dime: Gotta love that "Judoon platoon upon the Moon" joke. Played for Laughs when you realize they put that line in because when David Tennant pronounces "oon", he tends to get a bad case of Ooh, Me Accent's Slipping.
- Sad Clown: "You're quite a funny man and yet, I think, laughing on purpose at the darkness. Time you had some peace."
- Ship Tease: Martha is visibly stunned when the Doctor kisses her, and teases the Doctor as to his intentions when he invites her to become his companion.
- The Plasmavore uses a bendy straw to suck blood, much like how the Yugopotamians use bendy straws to feast on human brains.
- Martha compares the Slab drones to the motorcycle guy from the then-current Zovirax ads.
- The Doctor faking illness to investigate a hospital is similar to what Sherlock Holmes does in "The Dying Detective".
- Mr. Stoker is named after Mr. Stoker from Children's Ward, which Russel T. Davies was a producer on. The production team apparently thought it was a reference to Bram Stoker, so the sign on his office door says "B. Stoker."
- Some Kind of Force Field: The Doctor chucks a rock at the inside of the Judoon's force field, getting a ripple of static and an echoing note.The Doctor: Must be some sort of... [lobs rock] ... force field.
- Spare Body Parts: Martha gets her first real hint something weird is going on when she examines the Doctor... and hears both his heartbeats.
- Stable Time Loop: Used "for cheap tricks": when Martha first meets the Doctor, he stops in front of her on the street, takes off his tie, and walks off. When they meet at the hospital again, the Doctor can't ever recall meeting her. At the end of the episode, he goes back in time and takes his tie off in front of Martha in order to prove that the TARDIS is a time machine.
- Steal the Surroundings: An entire building was transported to the Moon so the Monster of the Week can locate a single person without them being able to escape.
- Stupid Statement Dance Mix: "You will be catalogued."
- Suspiciously Specific Denial: You are not a Replacement Goldfish, Martha Jones!
- Teleportation: The Judoon use a method the Doctor describes as a "hydro scoop" to transport the hospital to the Moon. It involves a localized stormcloud over the target, with the raindrops rising just before it kicks in.
- Temporal Paradox: The Doctor notes that crossing one's own timeline is dangerous and forbidden, "except for cheap tricks."
- Thanatos Gambit: The Doctor allows the plasmavore to feed on him so that she will register as an alien to the Judoon's scanners.
- Trophy Wife: Clive Jones' girlfriend Annelise, going along with his midlife crisis.
- Uncanny Family Resemblance: Martha Jones mentions she had a cousin that "never returned from Canary Wharf." Her cousin was also played by Freema Agyeman
- The Unmasqued World: After the Slitheen, Sycorax and Cybermen, Martha takes being zapped to the Moon in stride.
- Weirdness Censor: News reports claim everyone was just drugged, so none of this aliens on the Moon stuff happened. At least, according to Annelise. Francine retorts that she couldn't even handle watching Quiz Mania, let alone the news.
- Well-Intentioned Extremist: The Judoon. They're trying to stop a sociopathic galactic serial killer. They do this by transporting an entire hospital and everyone inside it to the Moon. Ultimately, they return it as planned, but it's still an incredible risk to take with the lives of probably hundreds of innocent bystanders. "Turn Left" reveals that, if the Doctor hadn't intervened, everybody but one man in that hospital (including Martha) would have suffocated. Similarly, the book Judgement of the Judoon opens with them forcing their way into a spaceship by driving an access tunnel through the hull, in order to ask the occupants about the Invisible Assassin. On discovering that they don't know anything, the Judoon leave... and don't think twice about retracting the access tunnel to leave a gaping hole.
- Wham Line: A sneaky one when Martha asks the Doctor if he's got a brother, and he replies "No, not anymore; just me." The Doctor's brother, Braxiatel, is a major character in the Expanded Universe (specifically in the Bernice Summerfield stories and in the Gallifrey audios) taking place before the end of the Time War.
- Worst Aid: Martha saves the Doctor's life ... with CPR when the problem was blood loss. Yes, she's supposed to be a medical student. Although, since the Doctor's a Human Alien, it's possible normal human medical techniques may not quite apply.
- Would Hurt a Child: The Plasmavore is wanted by the Judoon for the murder of the Child-Princess of Patrovolt Regency Nine. She insists the kid had it coming just for being cute.Florence: Oh, those blonde curls and that simpering voice. She was just begging for the bite of a Plasmavore!
- Wrecked Weapon: The sonic screwdriver is destroyed when the Doctor uses it on an X-Ray machine which fries it. He's distraught... for a few seconds, he then tosses it aside and by the end of the episode he's built himself a new (identical, so not a merchandising move) one.Martha: But it was that woman, Miss Finnigan. It was working for her, just like a servant.
The Doctor: [dejected] My sonic screwdriver...
Martha: She was one of the patients, but...
The Doctor: ... no, no, my sonic screwdriver!
Martha: She had this straw, like some sort of vampire!
The Doctor: I love my sonic screwdriver!
Martha: [chastising tone] Doctor!
[he throws the sonic screwdriver over his shoulder]
The Doctor: Sorry.
- You Are Who You Eat: The plasmavore already looks human, but has to drink human blood in order to scan as human.
- You're Insane!: The Doctor absorbs a lethal dose of radiation and then expels it through his foot. This results in him doing a one-legged dance across the room, complaining about how much it itches, before binning his shoe all while Martha watches.Martha: You're completely mad.
The Doctor: You're right. I look daft with one shoe. [bins the other one] Barefoot on the Moon!
- You Won't Feel a Thing!: Averted.Florence: I'm afraid this is going to hurt. But if it's any consolation, the dead don't tend to remember.