Donna: You just want to mate?
The Doctor: A mate! I just want a mate!
Donna: Well, you're not matin' with me, sunshine!
Written by Russell T Davies.
A little over a year after turning down the Doctor's offer of travel in the TARDIS, Donna Noble makes her way to the headquarters of Adipose Industries to investigate a new weight loss pill they have put out on the market. Unbeknownst to her, the Doctor is on his way to Adipose Industries for the exact same reason. This even extends to them both using the same "Health and Safety" cover story, with Donna entering through the front door and the Doctor entering through the fire exit.
The Doctor and Donna then both crash a press conference held by Adipose Industries head Miss Foster, neither noticing the other as Donna sits with the journalists and the Doctor watches from the projection booth. Penny Carter, the science correspondent at The Observer, asks what this drug does; Miss Foster gives them a lecture on the science of the pill, and the press conference ends. Over the afternoon, the Doctor and Donna sit down with different employees and get customer addresses; Donna also takes a pill-shaped golden pendant, a free gift that comes with the pills. While looking for the printer, the Doctor and Donna always miss each other by a second. While the Doctor gets pulled down and flirted with by his sales rep, Donna inadvertently grabs both sets, so he must return to get another copy, but they still don't see each other.
That night, the Doctor and Donna each go to a name on their client lists. Donna pays a visit to Stacy Campbell, who has lost 11 pounds on the Adipose treatment and is now preparing to dump her boyfriend since her weight is going down so nicely. Meanwhile, the Doctor interviews Roger Davey, who says that he's lost 14 kilos in two weeks, one kilo every night. Or, to be more specific, it's gone by exactly 1:10 am every morning. Roger knows that because every night at that time, without fail, something is setting off his burglar alarm and he's at a loss as to what it may be, and since he's woken up, he's taken to weighing himself then. The Doctor figures out that it's because of something going through Roger's cat flap. Not only does it let things in, it also lets them out. A necessity, given the Adipose pills' slogan, "The fat just walks away"...
Stacy goes to the bathroom, and Donna begins fiddling with her pendant. Unbeknownst to her, Stacy begins having stomach pains, and moments later, two humanoid cute and tubby pieces of fat force themselves out of Stacy's body and land in her sink. Donna, oblivious to what is occurring, then begins to investigate what's going on upstairs when she wonders why Stacy is taking so long. In her office at Adipose Industries, Miss Foster is alerted that there has been an unscheduled birth, and sends out a retrieval team in a van to retrieve the new Adipose children. The Doctor is also alerted of the birth via a Y-shaped hand-held tracker, and abandons his interview with Roger to chase it down. With Stacy having witnessed the Adipose child, Miss Foster realizes she knows too much and activates full parthenogenesis. Using her own pendant, forcibly converts the rest of Stacy into about a dozen more Adipose babies. Donna, who is now upstairs due to Stacy's screams, breaks into her bathroom just in time to see one last Adipose cheerfully wave at her, before jumping out the window.
The Adipose Industries retrieval team arrive minutes later, scoop up the new Adipose and zooms off in their van, just missed by both the Doctor and Donna, who both give up and head off in different directions, unaware they are just around the corner from seeing each other. Upon the collection team's return to the office, Miss Foster goes through her CCTV records with her henchmen to find out just who "borrowed" a pendant for industrial espionage. She exclaims "Oh, yes. There she is," as she pinpoints who she thinks is the mystery mole.
Shaken by what she's witnessed, Donna returns home...to now deal with her mother nagging at her about her unemployment. Donna sits at the table, ignoring her, as she tries to process what she's learned. She then goes to see her grandfather, Wilfred Mott, who is up at the allotments stargazing. He observes that she's just drifting through life, but she replies that she's waiting for the Doctor, regretting having turned down his offer to go travel with him after Lance's betrayal. When Wilf urges her to look for him, Donna admits she has, but he's hard to find (not knowing at all that Wilfred's encounter with him just this past Christmas). She asks him to keep an eye out for a certain blue box in the sky, and give her a shout if he finds it.
Back in the TARDIS, the Doctor is examining his readings, talking to himself for a moment... before remembering that he doesn't have Martha or Rose to bounce his findings off of. He stands there in silence.
The next morning, Donna and the Doctor both head back to Adipose Industries. Donna parks her car in an alleyway by the side of the building, and as soon as she leaves, the TARDIS materialises immediately behind it. Once again, they enter the same ways they did yesterday: Donna by the front entrance and the Doctor via the fire exit. The Doctor and Donna hide in the building until after hours: the Doctor in a janitor's closet in the basement and Donna in the women's toilets. Donna even goes so far to conceal herself as to pretend she is in church when her mother calls. She's interrupted mid-call when Miss Foster suddenly comes into the bathroom with her guards, searching for the thief. Donna tenses up and pulls her feet up, knowing she's been caught...until, much to her surprise, Miss Foster and her guards pull out Penny Carter, one stall to the left, who's had the same idea as Donna. Penny accuses Miss Foster of faking her results, but is silenced and quickly taken away.
As Penny is dragged to Miss Foster's office by her guards, Donna follows, peeking through the office door. The Doctor zips to the roof, fiddles with a window-washing bucket, and descends to the office window. He watches the same event from the other side of the room. They watch Miss Foster explain to Penny why she's come to Earth, and chides her for not figuring out how clever her choice of alias name is: "Foster", as in "foster mother", and as proof, produces one of the baby Adipose. Unable to quite see what's going on, both the Doctor and Donna pop their heads up... and finally spot each other. A funny scene ensues as they mouth frantic questions to each other while Donna does her best to mime her answers, all the while unaware that they are being watched by Miss Foster and everybody in her office. It's only when they realize Miss Foster has gone silent, and she asks out loud if she's interrupting them, that they realize they've been spotted.
Donna runs, while the Doctor locks the door with his sonic screwdriver and raises his window-washing bucket to the roof, before racing to the stairs. The pair hug, but have to keep running and head back to the bucket to lower themselves down for a quick getaway. As they run, Donna frantically tries to rundown how she tracked him here:
However, even though the Doctor locks the pulley with his sonic screwdriver, Miss Foster has a sonic pen of her own. She uses her sonic pen to cut the supporting cables on one side, making Donna fall out and hang on for dear life to the broken cable. Before Miss Foster can cut the other one, the Doctor uses his sonic to knock the pen out of her hand and into his; he uses it to open a window and swing inside, promising Donna he'll be right back to get her. Intrigued that someone with advanced technology has appeared, Miss Foster heads back in with her guards to confront the Doctor.
Inside, the Doctor arrives in Miss Foster's office and pulls Donna in through the window. Out of breath from her screaming, Donna asks if she's right in thinking it's always like this with him around. The Doctor confirms it with a smile and tells her it's time to run again. They rush out as Penny yells for answers; the Doctor tells her that as a reporter, she should just invent a story, which is what people in her profession are good at. He unties her via the sonic, and leaves after advising her to just Get Out! of here.
Miss Foster, with her guards, finally catches up with the Doctor and Donna in the main office; she notes that the Doctor must be an off-worlder due to his possession of sonic technology. The Doctor takes out the sonic pen he confiscated, noting that the design is sleeker than his sonic screwdriver. He asks for her real name, learning she is Matron Cofelia of the Five-Straighten Classabindi Nursery Fleet, Intergalactic Class, who has been hired by the Adiposian First Family to breed the next generation of the species from humans following the loss of their breeding planet. The Doctor wonders how losing a planet is even possible, but Cofelia dismisses it as politics she's not interested in. Cofelia ignores both Donna's protests about Stacy Campbell's death (which she passes off as necessary to keep her presence secret; she does feel bad that using an entire person's matter makes the Adipose born from them a little ill) and the Doctor's comment that "seeding a Level 5 planet is against galactic law".
The Doctor decides to make a last request before he and Donna get shot: does she know what happens if you use two sonic devices against each other? Cofelia hasn't a clue; for that matter, neither does the Doctor, so he points the two sonic devices at each other and turns them on. The result is a painful sonic feedback, which stuns Cofelia and her guards; Donna takes this opportunity to get the Doctor to follow her. Seeing that she cannot trap the Doctor, Cofelia fears that he might have alerted the Shadow Proclamation of her illegal actions; she decides to call the Adipose to collect the children that have been born already. Returning to her office, she finds Penny having wasted the chance to flee by staying to collect evidence, and has her guards tie her up again. Seeing that keeping her cover will not last, Cofelia activate the inducer, they're going into premature labour. Down in the basement, the Doctor and Donna head into the closet where he hid all day, which has a secondary inducer hidden in the back. He quickly uses the fact that Miss Foster had wired the building to stun her guards, who'd been sent in pursuit. Donna takes this chance to admit she was foolish to turn down the Doctor's original offer to travel with him and asks if his offer's still open. Back in her office, Miss Foster activates the main inducer, which sends a signal to the free pendants that will trigger the Adipose birthing process in the company's one million customers, converting fat, bones and internal organs... and killing the hosts in the process.
In a London wine bar, Sylvia Noble is having a girls' night out; one of them, Suzette Chambers, is an Adipose customer and "host". Suddenly, she and several other patrons at the bar begin to have convulsions as they begin to pop out Adipose babies, which also happens to Roger Davey back at his home (he stares bewildered as the Adipose uses his cat flap to leave the house). The Doctor manages to temporarily disable the process by unscrewing his Adipose capsule and attaching it to his inducer, but Miss Foster doubles the signal power. The Doctor begins to panic as he finds himself unable to stop the imminent deaths of a million people, but Donna offers him just what he needs: a second capsule to block the increased signal.
With the second capsule, the system overloads, saving the Adipose clients. However, ten thousand Adipose babies have now been born, and are now marching through the streets to Adipose Industries, causing traffic chaos. The ten thousand will have to do; the nursery is coming. As a benefit, the Doctor realize, now that the truth about the Adipose weight loss program has been revealed, it's highly unlikely that humanity will welcome the Adipose back to Earth; given that the spark of life needed could kill/convert them into Adipose.
A gigantic nursery ship arrives over London to collect the babies; while Sylvia gawps at it, Wilfred the one who's always believed in extraterrestrial life has his back turned towards his telescope in the other direction and his headphones on, missing the whole thing. As it arrives, so does a signal from the Adiposian First Family, which the Doctor listens to via the secondary inducer; he suddenly realises that it's no longer the humans, but Miss Foster, who is now in serious trouble.
The Doctor and Donna run onto the rooftop to watch several levitation beams carry the Adipose babies up to the ship. Having already seen firsthand what the Doctor can do to even children who he feels are a threat with the Racnoss, she asks if he plans to blow the Adipose up too, but the Doctor refuses to harm them as they're just children; they can't help where they came from. Donna openly notes that that is a marked difference from the last time they were in that situation; Martha's time with him seems to have changed him for the better. Smugly, the Doctor notes Martha fancied him. "Mad Martha, that one. Blind Martha, charity Martha!" is Donna's snarky response to that.
A child sees them as it ascends, waving at them. They wave back as the Doctor admits that as a weight loss plan, the Adipose birthing has its merits. They see Cofelia in another beam on her way up to the nursery ship. The Doctor pleads with her to get over to the roof; the Adiposian First Family is aware that their actions are illegal, which means they need to get rid of their accomplice. Cofelia dismisses the threat because she's the nanny but the Doctor remains worried, exclaiming, "Exactly! Mum and Dad have got the kids now they don't need the nanny anymore!" At that moment, the levitation beam carrying Miss Foster is switched off, and gravity is a cruel mistress as the Doctor comforts a horrified Donna. Immediately afterwards, the nursery ship leaves Earth.
Back on the street, the Doctor bins the sonic pen as Penny tied again to her chair flees the building, unable to cope with what's been happening; comically running off still tied up, she yells that the two of them are mad and she's going to report them for it. Donna points out, "Some people just can't take it." Then noting that "some people can!", Donna promptly drags the Doctor off to the TARDIS and is delighted to realise he parked near her car; it's just like destiny.
She promptly starts hauling a ridiculous amount of luggage out of the car boot and shoving it into the Doctor's arms, saying she's been ready to go for ages. The Doctor warns that it is a hard life but accepts her, saying that he just wants a mate. She misunderstands this to mean that he wants "to mate", saying he's just a "long streak of nothing" and exclaiming, "Well, you're not mating with me, sunshine!" The misunderstanding mostly resolved, Donna then calls her mum to say she's put the car keys in a certain bin for her to collect before asking a blonde woman to tell her mother, "That bin there". While Donna returns to the TARDIS, the woman a sad-looking Rose Tyler walks off down the street and disappears into thin air...
For her first trip, Donna tells the Doctor she wants to go "two and a half miles, that way." Back at the allotments, Wilf is still puttering about when he spots a certain blue box flying overhead. After first yelling for Donna, he takes a closer look through his telescope as the doors open, and realises she's in the blue box, waving to him from the doorway and so is that man from Christmas the Doctor! He starts whooping and dancing around in delight as the TARDIS spins away into space, happy she found what she was after: "Go on, girl! Go on, get out there!"
- Arc Words:
- "If that man's an alien, then he's alerted the Shadow Proclamation."
- "What d'you mean, 'the bees are disappearing'?"
- Artistic Licence - Space: Wilfred's telescope is at far too high an angle to see Venus. Venus, being the closer planet to the Sun, is always near the horizon around dawn and dusk, and thus never up high in the sky.
- Bait-and-Switch: After discovering that someone has stolen one of the Adipose necklaces, Miss Foster reviews the office security footage on her computer (with the monitor facing away from the camera) and says, "Oh, yes. There she is." Naturally, the audience assumes that Donna's been rumbled. It isn't until the following evening when Miss Foster comes to the bathroom to search the stalls for the mole that we find out that Penny Carter was who Foster had spotted.
- Bavarian Fire Drill:
- Both the Doctor and Donna, using the same cover story.Donna: [walks through the front door and quickly flashes an ID to the security guard] Donna Noble, Health and Safety.
The Doctor: [sonics the emergency exit and shows his psychic paper to a passing official] John Smith, Health and Safety.
- Later, when the Doctor is watching the presentation from the projection booth: "John Smith, Health and Safety... Film Department."
- Both the Doctor and Donna, using the same cover story.
- Blatant Lies: When Donna gets a phone call from her mother while hiding in the ladies' toilet, she says that she's whispering because she's in church. Sylvia clearly isn't buying it.Donna: Praying!
Sylvia: Well, it's a bit late for that, madam!
Wilf: [overhearing] What's she in church for?
Sylvia: Hush, you! Go up the hill!
- Body Horror: The Adipose form inside a human's body and then eject themselves from their host. It's cute Body Horror, but Body Horror nonetheless.
- Bond Villain Stupidity: The Doctor says "Wait wait, now hold on!" and his enemies listen to him and hold their fire, allowing him to use his sonic screwdriver and a sonic pen he'd gotten a hold of to create a sonic wave to disable the bad guys. Yes, they'll only fire on Cofelia's command, but still. See below.
- Bring the Anchor Along: Reporter Penny Carter gets tied to a chair twice by Miss Foster's thugs, the second time after ignoring the Doctor's advice to Get Out! At the end, she emerges from the building still tied to the chair to express her opinion that the Doctor and Donna are "mad" and that she's going to report them for "madness".
- Brown Note: What happens when you hold two sonic devices against each other (though apparently it doesn't affect Time Lords).
- Butt-Monkey: Captured and tied up several times; ultimately forgotten and has to run away with the chair she's tied to. Poor Penny Carter just cannot catch a break. Admittedly, she's not exactly doing a great job staying out of trouble, either.
- Chekhov's Gun: The Adipose necklace, and specifically the fact that the Doctor and Donna both steal one. It's a remote control for inducing birth.
- Chick Magnet: As the Doctor pretends to be a Health and Safety inspector, the telemarketer whose cubicle he stopped by slips him her number as he leaves. He gets rather flustered and tells her that accepting phone numbers is against regulations.
- Comically Missing the Point: Subverted. As quoted below, the Doctor assumes that the loss of the Adiposian First Family's breeding planet was literal when Miss Foster explains why she was hired, but Miss Foster's response implies that it was metaphorical, due to local politics. Miss Foster is the one who's missed the point, as the Doctor's assumption is absolutely correct.
- Continuity Nod:
- Contrived Coincidence: The Doctor and Donna investigating in the same building simultaneously, questioning workers in the same office at the same time, using the same printer, running down parallel streets and parking their transports in the same street without ever seeing the other is portrayed as pure coincidence. Until "Journey's End" implies it was fate via the Timey-Wimey Ball and one rebellious Dalek.
- Corporate Conspiracy: Miss Foster, head of Adipose Industries, is actually an alien nanny who intends to use her corporation to turn humans into Adipose for her clients at the expense of over a million lives.
- Corrupt Corporate Executive: Miss Foster is the head of Adipose Industries and a "space super-nanny". She's going to murder over a million people to give birth to a million Adipose for her clients.
- Crazy-Prepared: Donna carried round all the luggage she'd need to travel through time and space in the boot of her car for years, in case she ever met The Doctor again.
- Cute Little Fangs: The Adipose babies!
- Damsel in Distress: Penny Carter gets captured and tied up by Foster's thugs twice, the second time after ignoring the Doctor's advice to Get Out!
- Didn't Think This Through: Miss Foster is convinced that, as the "nanny" of the baby Adipose, she'll be welcomed with open arms by the First Family. There are two problems. One, once the children are back with the parents, they no longer need a nanny. Two, and more importantly, using a "level five" planet as a breeding ground is a strict violation of galactic law under the Shadow Proclamation... and Miss Foster is the only evidence that links the children to the Earth. Cue...
- Disney Villain Death: Miss Foster is elevated to the height of an office building by her employers, presumably to leave the planet. Then they cut off the beam. She takes the express route to the pavement.
- Dramatically Missing the Point: An unusual example relating to the season's Myth Arc. Miss Foster didn't realize that when her employers told her they lost their breeding planet, they meant it literally. Rusty was clearly trying to trip up the audience with this one.Miss Foster: I've been employed by the Adiposian First Family to foster a new generation after their breeding planet was lost.
The Doctor: What do you mean, lost? How d'you lose a planet?
Miss Foster: Oh, the politics are none of my concern. I'm just here to look after the children on behalf of the parents.
- Empty Piles of Clothing: All that's left of the unfortunate Stacey Campbell after she's fully converted into a bunch of Adipose babies.
- Establishing Character Moment: For anyone who missed or forgot her appearance back in "The Runaway Bride", Sylvia Noble first shows up treating Donna like a wayward teenager, then spends several hours nagging Donna about her choices in life. What a great mother she is."It's no good just sitting there, this isn't the 1980s anymore. No one's unemployed these days, except you!"
- Even Evil Has Loved Ones: Miss Foster does seem to genuinely consider the baby Adipose her own children, even though she's their nanny. Too bad her employers don't feel the same.
- Evil Gloating: Foster explaining her entire scheme to Penny, which also informs the Doctor and Donna about what her plan is.
- Exact Words: "The fat just walks away."
- Miss Foster mentions that the Adipose's breeding planet has been "lost," which both she and the Doctor take to mean metaphorically (as in losing territory during a war). "The End of Time" reveals that it is a case of this trope instead: Adipose III has literally been lost after being stolen by the Daleks.
- Explain, Explain... Oh, Crap!: A variation as the Doctor races to warn Miss Foster of the message he just saw.The Doctor: Listen, I saw the Adiposian instructions. They know it's a crime, breeding on Earth, so what's the one thing they want to get rid of? Their accomplice!
Miss Foster: Oh, I'm far more than that. I'm nanny, to all these children.
The Doctor: Exactly! Mum and Dad have got the kids now, they don't need the nanny anymore!
[Foster has one second to realize what the Doctor is saying before the transport beam shuts off]
- Expy: Miss Foster, of Miss Wormwood. Sarah Lancashire compared her to Mary Poppins:I see her as a slightly warped Mary Poppins. She's quite austere. She's a strong woman. When I first read the script, I thought, oh, well, of course she's a baddie...but the more I read it, I thought, "No, she's doing what she's doing for legitimate reasons".
- Face-Revealing Turn: The blonde woman Donna asks to tell her mother where Donna's left the car keys does this after Donna runs off, revealing herself to be Rose Tyler.
- Failed a Spot Check:
- It was established in series 1 and 2 that the TARDIS' noises are noticeable and carry some distance, becoming something of a Plot Point to other characters. Donna never hears it materialize behind her car.
- Donna fails to realize Penny Carter has been in the bathroom stall next to her, possibly for her entire wait there.
- For laughs. Wilfred Mott, stargazing with headphones on, fails to see the extremely loud and visible Adipose spaceship lower over the city behind him. (Although he does get to see the TARDIS at the end of the episode.)
- An ATMOS sticker is visible on the taxi when the driver speaks to Donna.
- The Shadow Proclamation, last mentioned in "Fear Her", is mentioned again in this episode.
- Rose's appearance at the end of the episode. She's supposed to be in an alternate universe.
- Planet Adipose III having been "lost".
- Donna mentions the bees disappearing.
- Genetic Memory: The newborn Adipose are birthed able to walk and know to return to the source the parthenogenesis signal. Other than that, their Ugly Cute little monsters, who don't know enough to not walk down the middle of the street.
- Get Out!: After the Doctor frees Penny Carter, he tells her to do exactly this. She doesn't listen and gets captured again.
- Gilligan Cut: The Doctor tells Donna he's locked the controls of the window washers' cart with a "sonic cage", so Miss Foster can't undo it unless she has a sonic device of her own, which is in his words "very unlikely". Naturally, the next thing we see is Foster wielding her sonic pen.
- Gravity Is a Harsh Mistress: Miss Foster has just enough time for an Oh, Crap! moment before the drop, looking for all the world like Wile E. Coyote. Possibly justified, there may be residual floaty from the lifty beam.
- Going for the Big Scoop: Penny Carter decides to hide in the ladies' room after hours in order to find out Adipose Industries' secret. It is thanks to her that Donna manages to avoid being captured.
- Ham-to-Ham Combat: The Doctor and Donna have what may be the first silent example in the history of film and television, when they spot each other through the windows on opposite sides of Foster's office.
- Improbable Infant Survival: Some Adipose get run over by a taxi, but the Doctor decides against violent action against them because they are children. Bonus points for not being born starving, unlike the Racnoss.
- Intrepid Reporter: Penny Carter, science correspondent for the Observer, seems to have figured out very quickly that Miss Foster's pills are very much a fraud.
- Is That a Threat?:The Doctor: Seeding a level five planet is against galactic law.
Matron Cofelia: Are you threatening me?
The Doctor: I'm trying to help you, matron. This is your one chance.
- It Works Itself: "The fat just walks away."
- Jumped at the Call: Donna is Playing with a Trope. She refused the call in her intro, then soon regretted that decision and went looking for the call so she could jump on it. She's ecstatic when she finds the Doctor.
- Last-Second Chance: The Doctor gives Miss Foster her "one chance", as he does to all his villains. As usual, she refuses.
- Leave No Witnesses: Miss Foster has Stacey fully converted when Donna accidentally causes Stacey to give birth to an Adipose. Miss Foster herself is one such witness.
- Limited Wardrobe: Donna, upon reuniting with the Doctor:Donna: You're even wearing the same suit! ...Don't you ever change?
- Locked Up and Left Behind: Penny Carter is captured and tied up by Foster's thugs twice, the second time after being freed by the Doctor and advised to leave. She turns up at the end carrying the chair she's still tied to, and somewhat peeved about the whole thing.
- Loud of War:The Doctor: Now hold on hold on! One more thing, before dying; do you know what happens when you hold two identical sonic devices against each other?
Miss Foster: No.
The Doctor: Nor me! Let's find out~!
- Ludicrous Gibs: Though not actually shown, this is what most likely happens to Miss Foster, since we hear a nice "splat!" sound effect after she falls to her death.
- May Contain Evil: The "may" part is unusually accurate the basic setting turns unwanted fat into a cute alien child, which is bizarre but doesn't do any harm. The Doctor even admits that "as a diet plan, it sort of works."
- Meaningful Background Event: If you pay attention to the Doctor and Donna's silent reunion, Miss Foster pauses while speaking to Penny Carter about ten seconds in.
- Meaningful Name:
- Missed Him by That Much: Played for laughs to the point of absurdity. Donna and the Doctor both sneak into the same office building through different entrances (using the same "health and safety" cover story) twice, crash the same product presentation (Donna sits with the journalists in the audience, while the Doctor watches in the projection booth), and both creatively acquire a list of customers from two office workers with cubicles literally three metres away and who print out the lists on the same networked printer without ever seeing each other (though Donna accidentally takes the Doctor's list). That night, we see both running down intersecting streets and stopping just short of the actual intersection. The next day, we have Donna parking her car and walking away, and mere moments later the TARDIS materializes right down the alley; and so forth. Donna even lampshades the trope by listing off a number of bizarre events that she investigated, believing the Doctor to have been involved, but dismisses the Titanic incident as a hoax... which was the only one that the Doctor was actually present for.
- Monster Is a Mommy: Technically, Miss Foster is a foster mother. Her employers are the real parents, and that distinction proves fatal when the Adiposian First Family realizes that their nanny is a piece of evidence linking them to a crime.
- Morality Chain: In her last appearance, Donna said that the Doctor "[needs] someone to stop [him]". She notes that Martha has been fulfilling that role until recently, and the Doctor himself admits that he needs "a mate".
- No Celebrities Were Harmed: Davies based Miss Foster on Supernanny star Jo Frost and Argentine philanthropist and politician Eva Perón.
- Not the Fall That Kills You : The Doctor and Donna are falling in a window-washing platform; the Doctor jams the mechanism and brings it to a stop within a second without either of them being injured.
- Obviously Evil: Miss Foster sounds like a slimy diet pill conwoman, because she is a slimy diet pill conwoman.
- Oh, Crap!: Miss Foster has just enough time to get this reaction across before she meets the pavement below.
- Planet of Hats: Donna packed a hat box.Donna: Planet of the hats? I'm ready!
- Punctuated! For! Emphasis!: Probably one of the only silent examples of this trope to date, thanks to two panes of glass and a room separating Donna and the Doctor and the amazing physical acting skills of one Catherine Tate. She mimes a Big "OMG!" that is also the aforementioned trope.
- Ridiculously Cute Critter: Baby Adipose are, as mentioned above, disturbingly cute.
- Save the Villain: The Doctor tries to warn Foster that the Adiposian First Family has betrayed her. "Oh, why does no one ever listen?"
- Sci-Fi Writers Have No Sense of Scale: If the one kilogram to one Adipose conversion rule is constant, then over half of Stacey Campbell's mass is unaccounted for after full parthenogenesis, considering the average person weighs about 70 kg and only 15 or so Adipose are created. It's possibly justified if the one kilo = one Adipose is specific to fat. Perhaps different bits (bones, organs, hair) of people have different conversion rates. If the actual number of Adipose created depends on volume, not mass, this makes sense: fat is so light that it floats in water; other tissues are denser than this, so a kilo of non-fat wouldn't have enough bulk to make an Adipose.
- Searching the Stalls: A variant. It turns out that the bad guys are actually searching for a different person, also investigating, who happens to be in the cubicle next to Donna's.
- The Adipose nursery ship when it's hovering over Adipose Industries has a very obvious similar appearance to the spaceships at Devil's Tower in Close Encounters of the Third Kind.
- In close-ups of Miss Foster during the press conference, all that can be seen of the company name "ADIPOSE INDUSTRIES" on the screen behind her are the letters "DUST", which was the catchphrase of Fat Fighter's Marjorie in Little Britain.
- Smug Snake: Miss Foster thinks looking after the Adipose makes her untouchable and that the family she's working for is practically indebted to her, no matter what the Doctor tries to say. A quick drop and sudden stop say otherwise.
- Soft Glass: Averted. When sonicking the window fails, Donna starts hitting it with a spanner... and doesn't have any more luck.
- Stock Episode Titles: 17 uses.
- Strange Minds Think Alike: The Doctor and Donna both use the same cover to get inside the office building, and both steal a necklace without being aware that the other is doing the same thing.
- Talking Is a Free Action: Subverted in the Doctor and Donna's first exchange mouthing words to each other across two panes of glass and a room as they observe Miss Foster. Foster's spoken dialogue to the reporter pauses conspicuously as they prattle on. At the very end of it, she asks, "Are we interrupting you?"The Doctor: [who, like Donna, is in complete silence] Donna...?
The Doctor: W-Wh... What...?
Donna: Oh... my... GOD!!
The Doctor: H-... How?!
Donna: It's me!
The Doctor: Yeah, I can see that!
Donna: Oh, this is brilliant!!
The Doctor: ... what the hell are you doing there?!
Donna: I was looking... for you!
The Doctor: What for?
Donna: I read it on the Internet... crept along... heard them talking... [Donna ducks down and slowly pops back up to illustrate her point] ...YOU!
Miss Foster: [the only person audible in the whole exchange] ... are we interrupting you?
The Doctor: ...RUN!
- Aside from the Russell T Davies Doctor Who standard, used by Miss Foster explaining how the pill allegedly works. Her long speech full of scientific-sounding words basically boils down to, "It's absorbed by fat tissue then breaks the fat down." Hilariously enough, it's revealed later that this explanation is a wholesale fabrication.
- It's used dramatically at one point, as the Doctor begins one of his usual technobabble explanations... then realizes he's speaking to an empty TARDIS. He lets the technobabble trail off and simply stares at the console.
- Tempting Fate: According to the Doctor, Miss Foster having a sonic device of her own would be "very unlikely". Cut to Foster unlocking the roof doors with a sonic pen.
- Title Drop: Miss Foster calls the Doctor and Donna "partners in crime".
- Unusually Uninteresting Sight: The Adiposian First Family somehow lost their breeding planet. When the Doctor tries asking how that happened, Miss Foster just shrugs it off.
- This winds up subverted later, though. It turns out this particular incident is far more important than it initially seemed. Miss Foster assumed that the Adiposian First Family had "lost" the planet as a country might "lose" territory in a war that is, it's been claimed by someone else. As it happens, the Adiposians were speaking literally: the planet has completely vanished from existence.
- Unwitting Instigator of Doom: A somewhat downplayed example; Donna is completely unaware that her fiddling with the Adipose necklace led to Stacey Campbell's death.
- Weight Loss Horror: Adipose Industries produces a special pill that makes your fat walk away: literally, it turns body fat into a little creature called "Adipose" that looks like an anthropomorphic marshmallow, which then leaves the host's body. Consuming too many Adipose pills may destroy a human's body completely.
- Wham Shot: Rose's sudden appearance towards the end of the episode, not to mention her disappearing with a TARDIS-sounding "whoosh".
- What Happened to the Mouse?: Averted. Though Penny Carter is abandoned for the action-packed chase sequence, spaceship arrival, and death of Miss Foster in the ending, she does emerge from the office still strapped to her chair prison and tells the Doctor and Donna that she'll be "reporting [them] for madness".
- What Measure Is a Non-Cute?: Donna asks the Doctor if he's going to blow up the tiny, adorable Adipose babies, but he doesn't as opposed to the last time they met, when he killed the omnivorous Racnoss babies.
- Why Don't Ya Just Shoot Him?: Even when Foster orders her guards to fire, they stop and wait for the Doctor to pull out his sonic screwdriver and the sonic pen and talk about what he's about to do, and they all 3 just stand there.
- Writers Cannot Do Math: The numbers for how many Adipose get created are all over the place. With a million customers, full parthenogenesis should have yielded way more than just "one million birthdays" like Ms. Foster predicted. The actual count ends up being about ten thousand, which implies that 99 percent of people taking the pill somehow didn't produce a single Adipose and the remaining one percent only produced a single Adipose each before the process was halted.
- You Have Outlived Your Usefulness: As the Doctor says, once mom and dad have their babies, they don't need a nanny anymore, especially a nanny that's an accomplice to a crime. Cue Miss Foster's short but impact-filled trip to the ground.
- "You!" Squared: The Doctor and Donna do this when they meet for a second time except they do it in mime, through a window.