Partners in Crime (TV story)

Partners in Crime was the first episode of series 4 of Doctor Who.

It also saw Sylvia Noble and Wilfred Mott return, as Donna's family. Donna's father Geoff Noble, however, was implied to have died offscreen, following the sudden passing of actor Howard Attfield. Importantly, Rose Tyler made a cameo appearance, heralding her eventual return later in the season.

This episode began the "Missing Planets Arc", with it being mentioned that Adipose 3 had been lost.

Synopsis
Donna Noble is determined to find the Tenth Doctor again — even if it means braving the villainous Miss Foster. But when the alien threat escalates out of control, can Donna find her Time Lord before the March of the Adipose begins at last?

Plot
Donna Noble, wearing a business suit, walks down a street on the way to Adipose Industries, as she is investigating them on their new weight-loss drug. Unknown to her, the Tenth Doctor is there for the exact same purpose. Both enter the Adipose offices through different entrances, and pass themselves off as employees of "Health and Safety".

Both the Doctor and Donna then crash a press conference held by Adipose Industries company manager Miss Foster, Donna sitting with the journalists and the Doctor watching from the projection booth. A science reporter, Penny Carter of The Observer, asks what this drug does; Miss Foster gives them a lecture on the science of the pill, and the meeting ends. The Doctor and Donna ask different employees for customer addresses; Donna also takes a pill-shaped golden pendant — a free gift that comes with the pills. Throughout their time at Adipose, the Doctor and Donna have multiple near-misses.

That night, Donna goes to the house of a woman named Stacy Campbell, who is preparing to go out on a date to dump her boyfriend now that her weight is going down so nicely — "I can do better than him now!" Meanwhile, the Doctor interviews another valued customer, Roger Davey, about his use of the drug. Roger tells the Doctor that he knows he's lost a kilo of weight every night by 1:10 AM — that's when he's always woken up by his burglar alarm. The Doctor deduces that this is because of his cat flap. Not only does it let things in, it lets them out too. As the Adipose slogan goes, "The fat just walks away..."

Stacy goes to the bathroom, and Donna begins fiddling with her pendant; the result is that a humanoid cute and tubby piece of fat forces itself out of Stacy's body. Donna, oblivious to what is occurring, then begins to investigate what's going on upstairs. Miss Foster is alerted that there has been an "unscheduled parthenogenesis", and sends out a squad team to retrieve the new Adipose children. The Doctor is also alerted of the "birth" via a Y-shaped hand-held device and runs off down the street to track it. Once Stacy witnesses the Adipose child, Miss Foster activates "full parthenogenesis", and Stacy's entire body is converted into numerous Adipose, leaving nothing but her clothing behind.

Donna, who is now upstairs due to Stacy's screams, breaks into her bathroom just in time to see an Adipose waving to her as it jumps out the window. The Adipose Industries retrieval team scoops 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 only a few feet away from each other. Miss Foster goes through her CCTV records with her henchmen to find out just who "borrowed" a pendant and spots her.

Donna cancels Stacy's cab, and goes home, only to find her mother nagging at her about her unemployment. Donna sits at the table, ignoring her, as she tries to get over what she saw. She then goes to see her grandfather Wilfred Mott, who is up at the allotments stargazing. He says she looks like he's drifting, but she replies she's waiting for the right man — the Doctor. When Wilf urges her to look for him, Donna explains she has — but that he is nowhere. 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 Martha Jones has gone. He stands there in silence.

The next day, despite protests from her mother, Donna takes the car to Adipose Industries, parking in an alleyway nearby. Shortly thereafter, the TARDIS materialises immediately behind it. The Doctor and Donna hide in the building until after hours: the Doctor in a caretaker's cupboard and Donna in the women's bathroom. Donna even goes so far to conceal herself as to pretend she is in church when her mother calls. Miss Foster suddenly stalks into the toilets searching for the thief — and, much to Donna's surprise and relief instead pulls out Penny Carter.

Penny accuses Miss Foster of faking her results. 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-cleaning crane and drops down to the office window. He watches the same event from the other side of the room. Unable to quite see what's going on, both pop their heads up — only to spot each other. 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.

Donna runs, while the Doctor locks the door with his sonic screwdriver and raises his window-cleaning cradle to the roof, before racing to the stairs. The pair finally meet, but have to keep running and head back to the window-cleaning cradle to lower themselves down for a quick getaway as Donna explains how she had searched for the Doctor by "[looking] for trouble". However, even though the Doctor locks the pulley with his sonic screwdriver, Miss Foster has a sonic device of her own. She uses her sonic pen to cut one side of the supporting ropes, making Donna fall out and leaving her hanging to the broke rope. 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 below Donna and swings her inside before following after her. Intrigued that someone with advanced technology has appeared, Miss Foster heads back in with her guards to confront the Doctor.

Inside, the Doctor and Donna have arrived back in Miss Foster's office via 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 with a smile and tells her it's time to run again. Donna rushes 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 runs out. However, Penny wastes the chance to flee by searching the office for evidence and is once more caught by Miss Foster and her guards. They tie her up again.

Miss Foster and her guards finally catch 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. Donna 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 that seeding a Level 5 planet is against galactic law.

The Doctor decides to make a last request: does she know what happens if you use two sonic devices against each other? Cofelia hasn't a clue; "Nor me. Let's find out!" the Doctor smirks, pointing his sonic and her pen at each other and turning them on. The result is a painful sonic feedback, which stuns Cofelia and her guards. The Doctor grabs Donna's arm and pulls her away. 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. 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 cupboard 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. Donna then admits she was a fool to turn down the Doctor's original offer to travel with him and asks if she can still come. 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 kill 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". Adipose start popping out of her, as well as out of Roger Davey back at his home. The Doctor manages to temporarily disable the process by unscrewing his Adipose pendant and attaching it to his inducer, but Miss Foster doubles the 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 pendant, to block the increased signal.

The second capsule overloads the system, and the Adipose clients return to normal; but ten thousand Adipose have now been born, and are now making their way to Adipose Industries, causing traffic chaos throughout London. The ten thousand will have to do; the nursery is coming. As a benefit, 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 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, and misses 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 first-hand what the Doctor can do to even children who he feels are a threat, the Racnoss children, 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." Donna jokes back to him.

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 Miss Foster, with just enough time to realise her fate, falls to her death as the Doctor comforts a terrified Donna. Immediately afterwards, the nursery ship leaves Earth.

Back on the street the Doctor bins the sonic pen as Penny — still tied to a 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 will report them for "madness". Donna points out, "Some people just can't take it" and then promptly drags the Doctor off to the TARDIS. Arriving in the alleyway, Donna is delighted to realise the TARDIS is parked just a few feet from her car; it's just like destiny!

Donna 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!" Once the misunderstanding is 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 girl to tell her mother, "That bin there". While Donna returns to the TARDIS, the girl, 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, and realises she's in the blue box, waving to him from the doorway — and so is the Doctor! He starts whooping and dancing around in delight as the TARDIS spins away into space, happy she found what she was after.

Cast

 * The Doctor - David Tennant
 * Donna Noble - Catherine Tate
 * Rose Tyler - Billie Piper
 * Miss Foster - Sarah Lancashire
 * Wilfred Mott - Bernard Cribbins
 * Sylvia Noble - Jacqueline King
 * Penny Carter - Verona Joseph
 * Stacey Harris - Jessica Gunning
 * Roger Davey - Martin Ball
 * Craig Staniland - Rachid Sabitri
 * Clare Pope - Chandra Ruegg
 * Suzette Chambers - Sue Kelvin
 * Taxi Driver - Jonathan Stratt

Uncredited cast

 * Drinker - Jon Davey

Individuals

 * The Doctor says he destroyed half of Martha Jones' life after she travelled with him and eventually left.
 * Donna leaves her car keys in a bin on Brook Street.
 * Rose Tyler suddenly appears back in N-Space on Earth, looks around disparagingly for the Doctor, and then teleports back out to Pete's World.
 * Wilf listens to "Twenty Four Hours from Tulsa".
 * Donna has been investigating sea monsters.
 * Melanie Darforth and Ellen Highbury are customers of Adipose Industries.

Devices

 * The Doctor uses a stethoscope to listen at the window of Adipose Industries.
 * Miss Foster has a sonic pen. Although it allows him to bypass deadlock seals when used in conjunction with his sonic screwdriver, the Doctor does not appreciate this device at all and deposits it into the trash.

Organisations

 * The Doctor and Donna pretend to be from Health and Safety.
 * The Collection Squad is part of Adipose Industries.

Planets

 * According to Wilf, Venus is the only planet in the solar system named after a woman.
 * Donna says she's ready for the Planet of the Hats after giving the Doctor a hat box to put in the TARDIS.

Places

 * Donna attempted to take a vacation to Egypt.
 * Veena visited Bahrain.
 * Roger lives on Candleford Street.

Influences

 * Russell T Davies based the character of Miss Foster on Supernanny star Jo Frost and Argentine philanthropist and politician Eva Perón, and Sarah Lancashire compared her character to Mary Poppins.
 * Davies' brief outlined a "cute" child-friendly creature shaped like a block of lard, similar to the Pillsbury Doughboy.

Story notes

 * This episode is dedicated to Howard Attfield, who passed away shortly after filming scenes for this episode reprising the role of Donna's father, Geoff Noble. As Geoff was to have been a recurring character in the season, the producers chose to remove Attfield's scenes and bring back Bernard Cribbins to play Wilfred Mott, the character he played in Voyage of the Damned; the character was retconned to become Donna's grandfather and renamed Wilf, although he was unnamed on screen, the character was called "Stan" in the scripts for Voyage of the Damned. Attfield's scenes were preserved and included on the subsequent Series 4 DVD release.
 * According to his memoir The Writer's Tale, Russell T Davies originally planned to introduce a new companion named Penny Carter in this episode, who he describes as 30-something, recently jilted by a boyfriend, and strong-willed in the vein of Donna Noble. When Catherine Tate became interested in reprising her role as Donna this idea was dropped, although a minor character in the episode, the journalist, was given the name Penny Carter.
 * This episode was broadcast at the earlier timeslot of 6.20. TV listings gave it a fifty minutes time slot rather than forty-five, stating it to be shown from 6.20 to 7.10. The actual episode clocks in at just under 49 minutes.
 * A certain shot shows an army of Adipose in the streets of London. This was extremely complex and took the series' CGI team, The Mill, more time than most shots used for the series to complete. They used the software called, which was created and used by , who created all CGI for The Lord of the Rings.
 * A scene was shown the day before airing on GMTV showing the Doctor and Donna Noble on a suspended window washing platform breaking in while Miss Foster cuts the cable with her sonic pen.
 * Pointing the functioning ends of a sonic screwdriver and a sonic pen at one another or, as the Doctor put it, "two identical sonic devices", creates a sonic feedback in the surrounding area.
 * The planet Adipose 3 is the first of the missing planets mentioned in this series. The mystery is solved in The Stolen Earth.
 * The scene with Rose was actually shot along with her scenes in Turn Left. It was removed from the episode when it was shown to the media. According to an interview in Doctor Who Magazine #396, the positive reaction to Billie Piper's surprise cameo (which was successfully telecast without any pre-broadcast revelation in the media thanks to this sleight-of-hand) led Russell T Davies to add a third surprise appearance by Rose to The Poison Sky, in addition to one already planned and filmed for Midnight (the Midnight footage was reused). Rose's return wasn't a complete surprise, however; besides media coverage of her return, a clip of Rose from Turn Left had also been included in the official Series 4 theatrical trailer several weeks earlier.
 * Miss Foster mentions the Doctor warning the Shadow Proclamation about her illegal activities, suggesting that they are an organisation rather than just a treaty; this was confirmed in The Stolen Earth.
 * The window cleaner cradle scene was intended for use in Smith and Jones but was cut and used here instead. In the first draft, the initial confrontation between the Doctor, Donna and Miss Foster was to have happened in the cradle, but budgetary and logistics problems meant the scene was moved to the sales cubicles area (and the Doctor's "sonic screwdriver plus sonic pen equals massive sonic feedback" diversion added).
 * The Adipose developed from Russell T Davies' idea that alien genetics were hidden in doses of a Botox-like drug, resulting in the people injected being overwhelmed by the genetic code and transforming into aliens; in his Writer's Tale he describes it as "Ladies Who Lunch/Lurch" (one of his cartoons included in the book shows his take on the idea).
 * This was the last episode until the 50th-anniversary special not to include a pre-credits sequence.
 * Additional material for the episode namely the reshoots featuring Bernard Cribbins in place of Howard Attfield, and Rose's cameo at the end was directed, uncredited, by Graeme Harper, according to the DVD commentary.
 * This is the first reference to disappearing bees, which is explained in The Stolen Earth. Although intended as a storyline reference, this is actually.
 * Miss Foster was originally called Miss Rattigan. It was changed because Russell T Davies felt that it better encapsulated her motherly role. The surname Rattigan would later be used in The Sontaran Stratagem.
 * Russell T Davies considered setting the story in suburban London, with a spaceship sealing off a section of the city under an enormous dome while an alien was hunted through the streets. The dome aspect was dropped because it was used in The Simpsons Movie.
 * When it was clear that Howard Attfield would be unable to be in the episode, Russell T Davies considered writing his character's death into the story arc, with Donna becoming a stronger person after dealing with the loss of her father.
 * The word "adipose" is the scientific term for body fat.
 * At one point, the story was set in a dilapidated old house that would hide a portal to another planet which had been overrun with vicious, dog-like Vorlax. The last survivors of this world had opened the portal to Earth in order to rid their world of the invaders.
 * The scene in which Rose Tyler appears was not included in the version of the episode previewed for critics, and while it had become common knowledge that Rose would appear in a later episode of Season 4, her presence in this episode was a successfully guarded secret until its first broadcast on the BBC. This music heard during her appearance derives from her previous appearance in Doomsday.
 * For the scene where the Doctor and Donna are reunited on either side of soundproof glass and thus have to mime their conversation, the script gave the lines they wanted Donna to mime (Donna does a little mime: "I came here, trouble, read about it, internet, I thought, trouble = you! And this place is weird! Pills! So I hid. Back there. Crept along. Looked. You. Cos they..."). Catherine Tate said that Russell T Davies had suggested that she might come up with something on the day. She improvised her mime during filming.
 * Originally, Colin Teague was supposed to direct as part of the third production block opposite The Fires of Pompeii. Complications with that episode led to it forming the block on its own, with this episode being made as part of Block Four and James Strong assigned.
 * The only location work outside Cardiff came when Picture Finance in Newport provided not only an area with sales cubicles, but also staffmembers to serve as extras in these scenes.
 * The Adipose were inspired by a stuffed toy Russell T Davies owned. Ironically, they would later become push toy. He later joked that he lost a fortune by licensing them under a BBC contract.
 * The scene of the Doctor meeting Donna on the stairwell had to be remounted a lighting problem which had afflicted the original version.
 * The scene where Donna and the Doctor investigate Adipose was difficult to film. The scene took thirty shots to complete, and David Tennant and Catherine Tate experienced problems avoiding each other on-screen.
 * For health and safety reasons, David Tennant was prohibited from performing his own stunts in the window cleaning platform. His only shot that required stunts was when he catches Miss Foster's sonic pen, a shot that took several takes to perfect.
 * As the episode mostly takes place at night, many scenes were filmed in the early morning.
 * The name Adipose comes from the scientific name for body fat, adipose tissue.
 * Further consultation with The Mill resulted in the ears and the single fang each Adipose has.
 * Had Penny Carter been introduced as the companion in this episode, she and her mother would be driving to visit her grandfather when they became trapped under a giant dome of alien origin. She would have been faced with the seemingly inncouous choice of turning left or right at a t-junction. The plan was to explore the alternative timeline in Turn Left.

Ratings

 * 9.14 million viewers (UK final)

Myths and rumours

 * It was rumoured that Miss Foster was actually the Rani. This turned out to be false.
 * It was rumoured that Rose would appear. This was true.

Studio

 * Upper Boat Studios, Treforrest

Location

 * Waterloo Gardens, Cardiff
 * Glan Rhymni, Tremorfa
 * Grange Well Park, Cardiff Bay
 * Odeon Cinema, Cardiff Bay
 * British Gas Building, Cardiff
 * Dominions Arcade, Cardiff
 * Picture Finance, Newport
 * Millennium Stadium, Cardiff
 * Crockherbtown Lane, Cardiff
 * Bar Icon, Cardiff
 * Nant Fawr Road, Cardiff
 * Kings Way, Cardiff
 * Fat Cats Restaurant, Cardiff
 * Tiger Tiger, Cardiff
 * Scott Road, Cardiff
 * Grangemoor Park, Cardiff
 * Franklen Road, Cardiff

Production errors

 * In every scene Miss Foster's guards change position.
 * When the Doctor and Donna are in the cradle, Miss Foster is seen cutting the cable on the right, the Doctor's side. However, the cable on the left, Donna's side is the one that snaps. This mistake is confirmed a few moments later; when Miss Foster says, "Now for the other one", she moves over to the cable on the left, which has clearly already snapped. This is realised in the episode commentary.
 * When the Doctor is erecting a sonic cage around the cradle controls, he puts the sonic screwdriver in his mouth, with the emitter facing to his left. When he turns to look at Donna briefly and takes it out of his mouth, the emitter is facing to his right.
 * At 17.21 the numberplate of the Noble family's car is YD55VHG. However, when Donna collects her bags from the car at 43.01 it has the numberplate LN54VKR.
 * In the scene with the Doctor and Donna outside the TARDIS, the rain in the alleyway stops and starts every time the angle changes. The production team had some difficulty filming this sequence due to both the weather, filming had to be rescheduled due to rain and then a very noisy nightclub nearby, as related by Russell T Davies in The Writer's Tale.
 * Miss Foster places an Adipose on her desk, but in the next shot, it's gone.
 * When the Doctor uses the sonic screwdriver and sonic pen in conjunction to incapacitate Miss Foster and her guards with the feedback, the sonic pen's emitter is shown to be closed, then in the closeup, it is extended, before being shown closed in the next shot.
 * The electrocuted guards start reacting to having been electrocuted before any electricity is shown to be generated.
 * The electrocuted guards disappear.
 * Stacy Campbell's name is clearly visible onscreen among other clients of Adipose Industries, and confirmed by Donna when she asks Stacy's full name, but the end credits refer to her as "Stacey Harris".
 * In the Adipose Industries toilets, a poster on the wall states that "De Rossi's Wine Bar is dedicated to keeping these facilities clean at all times" and goes on to say that "we check our facilities at regular intervals". Against all other evidence, this would imply that the scene is taking place at De Rossi's Wine Bar. It would also suggest that a scene was to originally be set in the toilets of the Wine Bar.

Continuity

 * Donna and the Doctor refer to many instances the last time they encountered each other, including the Doctor drowning the Racnoss children. Donna declined the Doctor's offer to travel with him then, but regrets the decision and accepts this time. (TV: The Runaway Bride)
 * The Doctor mentions how Rose Tyler is still lost, (TV: Doomsday) and how his most recent companion Martha Jones suffered while adventuring with him. (TV: Last of the Time Lords)
 * The Doctor and Donna constantly missing each other by a fraction resembles the First Doctor and Vicki constantly missing Barbara Wright and Ian Chesterton while in Rome. (TV: The Romans)
 * Rose Tyler appears, briefly returning from the parallel universe in which she was locked. (TV: Doomsday)
 * The effect of pointing the sonic pen and sonic screwdriver or, as the Doctor put it, "two identical sonic devices", at one another is remarkably similar to an effect of a sonic device used by Toshiko Sato. (TV: Fragments) This trick was also done by the Fourth Doctor and the Eighth Doctor to enter The Master's TARDIS when trapped in a pocket dimension (AUDIO: The Light at the End)
 * Reference is made to disappearing bees and a missing planet. (TV: The Stolen Earth)
 * One of the taxis has an ATMOS sticker on the windscreen. (TV: The Sontaran Stratagem / The Poison Sky)
 * In a parallel world, sixty million Americans were converted into fat. Adipose Industries had targeted the United States rather than London, as the city had been destroyed and the entire South of England flooded by radiation when the Titanic crashed. (TV: Turn Left)
 * Roger Davey says he is not a cat person, which makes the Doctor reflect on his past encounters with "cat people". (PROSE: Fairy Tale of New New York, TV: Survival, New Earth, Gridlock)
 * A catflap is examined as a method of either entry or exit for an alien threat. (TV: Rose)
 * The Shadow Proclamation is mentioned. (TV: Rose, The Christmas Invasion, Fear Her) The Doctor will later take Donna to meet them. (TV: The Stolen Earth)
 * Donna refers to the Titanic replica over Buckingham Palace, saying it must have been a hoax. (TV: Voyage of the Damned)
 * Donna and the Doctor's mimed reunion echoes a similar situation involving the Third Doctor and Jo Grant. (TV: The Sea Devils)

Home video releases

 * This story was released in the Series 4 DVD box set in November 2008 along with the rest of the series.
 * It was also released as Series 4 Volume 1 in a vanilla edition with The Fires of Pompeii and Planet of the Ood.