The Stolen Earth (TV story)

"Welcome to my new Empire, Doctor. It is only fitting that you should bear witness to the resurrection - and the triumph - of Davros, Lord and Creator of the Dalek Race."

- Davros

The Stolen Earth is the penultimate episode of the fourth series (season 30) of Doctor Who.

Synopsis
When the Earth is stolen from its orbit and placed in another galaxy with 26 other stolen planets, the Doctor's secret army of allies comes together to defend the Earth from the New Dalek Empire. With battles raging on the streets and in the sky, the Doctor and Donna confront the Shadow Proclamation to find the truth; however, a fearsome old enemy waits in the shadows.

Plot
Having seen the signs, the Doctor and Donna returned to Earth to find everything in order. Donna pressed the Doctor for an explanation of Rose's unexpected reappearance; the Doctor says that, if Rose can cross from her parallel world to Donna's parallel world, then the walls of reality are breaking down. But, with Earth apparently safe for now, they return to the TARDIS and prepare to stop the walls breaking. The TARDIS rumbles with an apparent earthquake. The Doctor and Donna rush to the doors and fling them open--to find that they are hanging in space. The Doctor checks the readings and realizes they have not moved, but the Earth has gone missing. It has been stolen.

At UNIT's New York base, Dr Martha Jones, regains consciousness after an earthquake to find UNIT in chaos and its personnel panicking. One hysterical colleague screams at Martha to look at at the sky. In Torchwood Three, Captain Jack Harkness blames the Rift for the brief but violent earthquake that has just devastated the Hub. After making sure that the other members of Torchwood Three -Gwen Cooper and Ianto Jones - are all right, Jack heads outside to survey the damage. Ianto and Gwen look at the computers and Ianto realizes that, whatever the problem is, "it's a bit bigger than South Wales".

At 13 Bannerman Road, Ealing, London, Sarah Jane Smith and her son Luke comment on the earthquake - and wonder why, if it was only 8 a.m., when the quake struck, it is now dark outside. They approach the nearest window and look outside. In Chiswick, London, Donna's mother Sylvia and grandfather Wilfred aren't sure what has caused the earthquake. As they step ouside their home, Sylvia looks at the sky. On the street in London where the TARDIS was parked, Rose Tyler materializes. She is carrying a large gun. She looks up and, alone of the Doctor's friends, does not seem surprised. She declares that "it's only just beginning..."

The familiar Earth sky is gone. The sun is gone. The constellations have been replaced with strange new ones. And twenty-six new planets have appeared in the sky. Back on board the TARDIS, Donna demands to know if her family are dead. The Doctor does not know, and decides they have to get help. They set a course for the Shadow Proclamation.

At Sarah Jane's house, alien supercomputer Mr Smith picks up readings of a fleet of 200 spaceships apparently headed towards Earth. At UNIT, American UNIT leader General Sanchez enters tells all soldiers and staff that UNIT commander Geneva has declared a Code Red Emergency. Martha tells him that she has tried to phone the Doctor, but the signal is dead. The number calls anywhere in the Universe, but the signal is being blocked by some unknown force. Sanchez notes that they will likely find out soon because the fleet is coming into orbit.

Martha manages to call Jack, who says that he has heard anything from the Doctor either. Gwen calls her husband, Rhys, and tells him to stay indoors and call her mother. Meanwhile, Rose is walking along the streets of London. She threatens a pair of looters with her gun and looks at the computer screen in the bank they were robbing. She then looks at the readings.

At Torchwood Three, the team see the spaceships. Mr Smith tells Sarah Jane that the ships have a message for the human race. He puts it through. It consists of a single repeated word: 'EXTERMINATE!' The message is heard on all frequencies, including in UNIT and the speakers at Torchwood Three. The enemy are the Daleks. Upon hearing the message, both Jack and Sarah become very emotional and Jack says "I'm sorry. We're dead."

Rose hears the message and heads outside to see a massive Dalek spaceship flying over London, destroying everything in its path. Martha looks outside to see Dalek spaceships flying everywhere, destroying New York. Aboard a massive spaceship at the heart of the cluster of planets, the Daleks finalise their plans. The Supreme Dalek, a red Dalek with extra paneling, declares that the Crucible will soon be complete, and that the Daleks are the masters of Earth.

Far back across the Universe, onboard the TARDIS and unaware of the unfolding destruction on Earth, the Doctor and Donna arrive at the Shadow Proclamation and are held at gunpoint by its rhino-headed guards, the Judoon. The Doctor manages to convince them they mean no harm and need help. A female member of the Proclamation tells the Doctor that in fact 24 planets have been stolen. Donna asks about Pyrovillia, but the Judoon captain tells her that Pyrovillia is a cold case, and it disappeared over 2000 years ago. Donna asks about the Adipose Breeding Planet and the Doctor realizes that planets are being snatched out of time as well as space. The Doctor heads over to the computer and shifts it into 3D. He adds Adipose 3, Pyrovillia, and the Lost Moon of Poosh.

Hello everybod. Doctor Who rocks.

Hello everybody. Doctor Who rocks.

Daleks

 * Wilf uses a paintball gun as a weapon against the Daleks by shooting paintballs at their eyestalks, referencing the popular method of incapacitating a Dalek: blinding them. However, it seems that the Daleks have been redesigned with this weakness in mind as the paint simply melts off the eyestalk after coming into contact with it (and at the same time replying "My vision is NOT impaired").
 * Dalek Caan predicts the most "faithful" companion will die.
 * Caan referred the Doctor as "Dark Lord". (The Doctor is probably referred to in this way due to being the cause of death and destruction, from the point of view of the Daleks. ) He has also been known by the Daleks as the Ka Faraq Gatri or the 'destroyer of worlds' and also "The Oncoming Storm".
 * The new Daleks are said to be Davros's "children" as they have been grown from his own cells.
 * Davros makes a quick reference to Dalek Emperor.
 * The Daleks' weaponry has seemingly been updated to include a "maximum extermination" setting, capable of destroying an entire house if three Daleks fire at the same target.

The Doctor

 * The Doctor first went to the Medusa Cascade when he was "a kid" at the age of 90.
 * A possible reference to the lyrics of the song "The Stowaway" heard while the Doctor was on the Titanic. The song predicts that the Stowaway will be "lying with his love", which is exactly what the Doctor is seen doing after he is shot and again just before he begins to regenerate.

Last Great Time War

 * Doctor says that Davros died in the very first years of the Time War, suggesting that Time War has lasted several years.

Planets

 * Some of the missing planets mentioned are: Callufrax Minor, Woman Wept, Clom, Pyrovillia, Adipose 3, Poosh and Earth.
 * The missing planet Callufrax Minor may be a reference to Calufrax, the miniaturized planet and Key to Time segment of The Pirate Planet. Ironically one of the co-stars of that Tom Baker-era serial, Bruce Purchase, died only a few weeks before the episode was broadcast.

Technology

 * There is reference to an object called an "Osterhagen key", but no explanation is given as to its function, origin or purpose. Significantly, while Harriet Jones is aware of its function and forbids its use, and Martha is also aware of what it can do, Jack Harkness and Torchwood have no idea what it is, even though they know about the other top-secret Indigo project.
 * Harriet Jones uses the subwave network to put the Doctor's 'secret army' in contact with each other, it utilises Sub-wave communication developed by the Mr Copper Foundation.

Story notes

 * This episode was the last of Series 4 to have its title revealed.
 * This is the fourth time that the Daleks have returned with a leader in a finale. In DW: The Evil of the Daleks they returned led by their emperor; in the 2005 finale, The Parting of the Ways, the Daleks were led by the Dalek Emperor; and in 2006 finale, Doomsday, Dalek Sec led the Cult of Skaro. The Other Dalek two parter in 2007 Series was shown as the 4th & 5th Episodes of the Series (Daleks in Manhattan and Evolution of the Daleks).
 * Davros refers to the Doctor's allies as the Children of Time.
 * The Doctor starts to regenerate yet again, acting as a cliffhanger.
 * The Doctor's severed hand is seen bubbling at the end of Turn Left and during this episode as well. When in Jack Harkness's possession, the bubbling signaled the Doctor's presence, but in the Doctor's possession the bubbling has signaled the presence of other Time Lords. Could the Doctor's severed hand have a sentient mind?
 * Davros and his command ship were lost in the first year of the Time War. Dalek Caan managed to save Davros, at the cost of his own sanity.
 * The Doctor states he tried to save Davros before his ship was lost in the first year of the Time War.
 * The "To Be Continued" before the end credits is different from the others previously used. There is also no sneak peek of the next episode.
 * When Harriet Jones contacts Captain Jack, Martha Jones and Sarah Jane Smith, the contact tone is the same tone used by The Master to control the populace under the Archangel network.
 * For the first time, the opening credits incorporate not two or three names, but six, adding Freema Agyeman, John Barrowman and Elisabeth Sladen to the Tennant, Tate and Piper credits of the previous week. The typeface used for these credits is slightly different than that usually used. In addition, several "overflow" cast credits are featured over the first scene after the opening sequence, a first for the series (Penelope Wilton, Adjoa Andoh, Eve Myles and Gareth David-Lloyd). Incidentally this is the first time Elizabeth Sladen's name has appeared in the opening credits. This is the first time all of the Doctor's "main" companions since the revival of the series began (the female leads) have all been credited at the same time; it is not, however, a complete listing of all the revival-series companions as Noel Clarke, Kylie Minogue (Astrid Peth) and Bruno Langley (Adam Mitchell) are not included.
 * Russell T Davies's pattern of using the same surnames is the most notable in this episode with Martha Jones, Francine Jones, Harriet Jones and Ianto Jones. Francine and Martha are related (mother and daughter).
 * Scientist and author Richard Dawkins has a cameo as himself. Dawkins is married to Lalla Ward, the actress who portrayed Romana II. The two were introduced by Douglas Adams, who met Ward in his capacity as the show's script editor.
 * The claws of the Daleks in Crucible is very similiar to ones in Doctor Who And The Daleks- Movie, but with eight fingers instead of two.
 * Dalek Caan predicts the most "faithful" companion will die.

Ratings
To be added

Myths and rumours

 * The presence of Davros in this episode had been rumoured for a long time before broadcast. An associated rumour suggested that the episode would reveal that Donna was actually Davros in disguise or Caan mutating himself into Davros.
 * It was also rumored on the fan boards that Patrick Stewart or Ben Kingsley might have been cast as Davros, given media reports of his interest in appearing in Doctor Who after it was announced that he and Tennant would perform a season of Shakespeare together in 2008. Ultimately, Julian Bleach was revealed to be playing the character.

Filming Locations

 * Cardiff
 * Pontypridd

Discontinuity, Plot Holes, Errors

 * If the Reapers appeared and tried to destroy all life on Earth last time there was an attempted rescue in time to prevent someone's death, why does this not occur with Dalek Caan and Davros? The presence of two sets of the Doctor and Rose had made that point in time/space particularly vulnerable. But there where two Dalek Caans at this point as one was fighting in the time war. The timelords where still alive then so they could easily fix the problem. False. The Cult of Skaro had escaped the Time War in the Void Ship. Dalek Caan was not present. Also in Father's Day, in order for the Reapers to attack, Rose had to make physical contact with her past self (although they'd still appeared long before Rose made contact with herself, didn't they? So, y'know, that's kind-of a moot point.) Also saving Davros didn't create a paradox, unlike in Father's Day were A) they saw themselves, and B) the whole point of them being there was to save Pete if Pete died no point to go back, and therefore Pete would have died
 * It is not explained how the Daleks know of Harriet Jones. Presumably this is for comedic effect, serving only to continue the running gag. During the doomsday episode the Dr Singh character had his memory taken and he would have known about Harriet Jones and even though Dalek Caan is insane Davros is aware of current events.
 * Normally when a Dalek exterminates someone the beam normally hits them and disappears but when The Doctor gets exterminated you can clearly see the ray go through him and come out the other side. The beam did not go through him: it went past him, only touching him slightly. Also, his entire body did not glow; only a portion did, which suggests that the beam did not do full damage (though still enough to cause a regeneration apparently).
 * At the end of Turn Left Bad Wolf was on the TARDIS. It's not there now. They've travelled to Earth, as per Rose's request. Having arrived, there's no further need for the Bad Wolf message. In addition, it's been suggested that the Bad Wolf wording might have been put there by the chameleon circuit; perhaps the Doctor was able to rectify this, or the TARDIS itself decided it didn't need it anymore.
 * The TARDIS didn't translate the 'Judoon-speak', though the Doctor could understand it. This could have been similar to the Hath. This may also have been done to give a bit of humour to a much serious episode. Later in the episode we can understand the Judoon, maybe it just takes time to work. Maybe it can not be translated into English because there is no English for it, it is clear that it is used as some form of clearance code, or something along those lines. Or perhaps Translations are not used in the Shadow Proclamation for legal reasons. Or Doctor understands Judoon language(as being able to respond to Judoons), so no need to translate. Or maybe it translated for the Doctor and Donna, but didn't translate for us, the viewers, because the way Donna looks at the Doctor when he is speaking seems as though she understands him. Also, the Judoon are probably actually speaking English later on in the scene, since in Smith and Jones, the Judoon used a human's words to be able to speak English. Also the "Judoon-Speak" may have only been developed and widely used after the construction of the Doctor's TARDIS meaning that it would not be programmed into the translation circuit.  "Ma-Ho" has been suspected of being similar to his line in The End of the World of "She's my plus-one." or similar introduction of his companion after presenting his personal credentials.
 * When Harriet Jones transfers control of the sub-wave network to Torchwood, the map circles an area in Swansea, not Cardiff. Russell T. Davies was born in Swansea, this may be an intentional error.
 * When Jones' sub-wave system seeks out those who have worked with the Doctor, only the companions of the Tenth Doctor are singled out, not other past companions and/or acquaintances who might have worked with previous incarnations.Harriet Jones states the sub wave only finds people with the capacity to contact the Doctor. Presumably this refers to the current incarnation of the Doctor (as opposed to someone trying to contact, say, the Sixth Doctor), thereby disqualifying companions such as Ian Chesterton or Tegan Jovanka, who presumably have no access to things like "superphones".
 * Donna indicates she has no idea what regeneration is, even though she was present when Martha referenced it in The Doctor's Daughter (She might not have understood what was meant at the time).
 * When Martha is about to engage the Project Indigo device, there is a scene where she says goodbye to Captain Jack over the phone, using a blue-tooth headset. In the shot immediately preceding, she is not wearing the headset. In the shot immediately following, right before she activates the device, she is seen removing the headset.
 * Why did Harriet's computer screen turn off just because she died? Presumably the computer was destroyed as well as Harriet, perhaps by the Daleks' extermination rays. They might not have 'exterminated' her, but her computer in an attempt to stop the signal. Also, if the subwave finds the people who can contact the Doctor, then it must somehow link with the people themselves. This is demonstrated by the sub-wave finding Rose, even though the nearest computer is not her own. Harriet's death would therefore have severed the connection.
 * How did Captain Jack know exactly where to teleport to shoot the Dalek that had shot The Doctor? He probably tracked the TARDIS location. The numbers 4 and 9 were to reactivate his vortex manipulator. He also appears to have arrived facing the Dalek, so his reflexes would have come into play.
 * If Rose asked her "Control" to lock on to the TARDIS and transport, why did she end up at the other end of the street? Even a machine as good as the TARDIS can make slight errors. The control did reasonably well to land her quite near to the TARDIS, especially since we don't yet know where "Control" is located; if it's on Pete's World or Donna's World, accuracy may have been difficult.
 * How can Davros have an organic body when he was just a head in Remembrance of the Daleks. Presumably he generated a new body, considering he's able to create Daleks from his own cells.  Davros wasn't just a head in Remembrance of The Daleks, his body was just covered with wires. Are you sure your not confusing this with the decoy head he used in Revelation of the Daleks?
 * Though, if this is true, why does he have a cybernetic hand (presumably a replacement for the one lost on Necros in Revelation of the Daleks) instead of an organic one? Possibly because a cybernetic hand is stronger than an organic hand. His severed head form in Remembrance could have been a decoy, as was his severed head form in Revelation.


 * Dalek Caan didn't have emotions, so how can he laugh or go insane in the first place? Caan was a member of the Cult of Skaro, who were made to think like the enemy, i.e. having names and some emotions. As indicated in dialogue in this episode, emotions are discouraged, but still exist. There are also other examples of Daleks displaying anger, pride, and even a sense of humor (albeit sarcastic and dry) in past episodes (for an example of the last, reference the "pest control" comment directed at the Cybermen in Doomsday). Not only that, but Davros, when he created the Daleks, didn't remove all emotions: just those which he considered a weakness, such as mercy, compassion and forgiveness. Not to mention the fact that emotions are not a necessary component of insanity.
 * Ianto is seen watching Paul O'Grady, but it was said earlier in the episode that it was a Saturday. Paul O'Grady is not aired on a Saturday. A possibility is that the move of Earth has taken time or time has skipped forward since the mention of the date was prior to the move. Perhaps Ianto uses Sky+. Also, there is clear indication that, on earth at least, at least a few hours might have elapsed.
 * When a Dalek turns around and implies, "New location, Torchwood", the blue light in it's eye is switched off as if it has been blinded and does not come on until a few seconds later.
 * The apparent death of Harriet Jones puts paid to the Ninth Doctor stating that she was destined to serve three terms as PM and lead Britain into a new golden age (DW: World War Three). In several episodes, the Doctor has stated that history can be rewritten and only certain fixed points remain unchangeable. Presumably Jones is one of those changeable points. Also, Turn Left addressed the notion of alternate timelines stemming from choices; perhaps the Ninth Doctor was referencing what turned out to be an alternate timeline created when his next incarnation set in motion the events that would end her career (DW: The Christmas Invasion). Also, it should be noted that until the events of Journey's End play out, it remains to be seen if Jones has actually been killed.
 * Television, cellphone and satellite communications continue to work, even though by rights when the planet moved anything in orbit should have been lost. Evidently when the Earth was moved whoever did it decided to include its satellites as well. One does not need satellites for ground-based television or cellphone broadcasts.
 * What about the Moon? There's no indication it was moved with the Earth, so is it going to drift away? Objects in space often move slowly relative to the Earth, so even if the moon were suddenly cut free (a la Moonbase Alpha in Space: 1999) it would take awhile for it to be lost forever, giving some time for the planet to be returned to its proper place. If the Earth is gone then the moon will be attracted to the biggest gravitational force near it which would be the Sun, keeping it in its general position for awhile, at least.
 * This episode is set in 2009, with hundreds of Daleks invading Earth. Not to mention the previous encounter in Doomsday, how does the human race not know of the Daleks in the 2005 episode Dalek, set a few years after these events? This has yet to be determined; possibly the timeline in the "Dalek" episode has been negated. Also, in this episode, Gwen displays no knowledge of the Daleks despite the events of Doomsday. The episode 'Dalek' was set in 2012.  There were no modern-day Daleks in the 2005 series.
 * If the Earth has changed co-ordinates how is Rose able to find it? Possibly there is some sort of connection between our Earth and the parallel Earth regardless of their positions in space and time.
 * Why did the rift move with the Earth? Shouldn't it have stated behind the way the TARDIS did? If the Rift stayed in the exact same point in space-time then it would only be in Cardiff once a year, so it's safe to assume that the rift is in some way locked to the physical location of the city of Cardiff somehow. Without knowing more about the Rift it's difficult to say for sure. There is also, according to modern physics, a theory called frame dragging, where a gravity well may drag spacetime along behind and around it, like the wake of a boat through the water.  This may explain why the rift stayed still relative to the planet.
 * The TARDIS stayed in place even when the Earth moved. But in The Impossible Planet the TARDIS fell down after the floor was removed. The whole planet was teleported away from the TARDIS; ergo no gravity. Exactly why the TARDIS wasn't transported as well -- especially given Davros' stated desire to meet him again -- has yet to be explained; perhaps it was in some sort of "pre-dematerialization" state that prevented it from being moved, too.  Maybe the hand-brake was set. Uh...Davros never said that he wanted to meet the Doctor again. Besides, the Dalek Supreme made it sound like they wanted to specifically AVOID any encounters with the Doctor if possible.
 * The transportation effect of Jacks vortex Manipulator is different from seen previous in The Sound of Drums. In The Sound of Drums Jack and the rest of the party travel through both time and space, whereas in this case he only travels through space- as such he gets the same visual effect as Martha did when she teleported.
 * Why do Gwen and Ianto use machine guns against the Dalek invading Torchwood when they have all sorts of captured alien technology lying around? Perhaps none of the technology at hand was considered effective as offensive weaponry. Firearms have been shown as effective against Daleks if one knows where to fire (DW: The Parting of the Ways, etc.).
 * There appears to be a double-typo in the on-screen reference to the missing world Callufrax Minor. First, Minor is spelled "Minorr" (This might be the spelling used by the Shadow Proclamation, however), plus if this is intended to be a reference to the Tom Baker-era planet Calufrax, then the name should have one L, not two The daleks most likely invaded those planets before the earth was moved.
 * Assuming some of the other planets are inhabited, shouldn't Earth be bombarded with signals? (Perhaps whoever moved the planets is blocking communication, or the communication standards of the different worlds are not compatible.)
 * If the Earth has moved then how come it hasn't frozen over without the sun to keep it warm and maintain it? Jack explains this. Darvos had the insight to maintain the heat and atmosphere of the planets. Yeah, try actually PAYING ATTENTION next time.

Continuity

 * This episode marks the first on-screen appearance of the Shadow Proclamation, first mentioned in DW: Rose. This episode reveals that it is an organization, not just a treaty.


 * This episode also marks the first appearance in the main Doctor Who series of the following characters and locations from the spinoff series: the Torchwood Hub, 13 Bannerman Road, and the Mr Smith computer. Also referenced for the first time in the parent series are Owen Harper, Alan Jackson, Rhys Williams and Mary Cooper. However this is not the first reference to Toshiko Sato as she had previously appeared in Aliens of London or Gwen Cooper, Ianto Jones, Luke Smith, Clyde Langer and Maria Jackson as they were all mentioned in the previous episode, Turn Left, which also referenced the Sarah Jane Adventures villain The Trickster.


 * For those who have not watched the spin-offs, the episode provides a brief reference to the deaths of Owen and Tosh in Torchwood, but offers no explanation for the absence of K-9 and the origin of both Luke Smith and Mr Smith in The Sarah Jane Adventures (indeed, the episode includes a potentially confusing reference to the teenage Luke being Sarah Jane's son).


 * The Medusa Cascade, first mentioned in DW: Last of the Time Lords also plays a key role in the episode.


 * The Valiant last appeared in DW: The Poison Sky to help UNIT with attacking the ATMOS Factory. In this episode, it is seen being swarmed (and most likely destroyed) by a huge group of Daleks using 'maximum extermination'), which they also use to exterminate a man that rebels against their order of human surrender. This is the first time this power has been used. When building the new Dalek army, Davros most likely improved the Daleks' weaponry. The Daleks have also used maximum extermination when attacking 'Hooverville'.


 * The Doctor deposed Harriet Jones in DW: The Christmas Invasion.


 * The gun that Captain Jack used to kill the Dalek with was the same gun he used in DW: The Parting of the Ways.
 * The Doctor previously disabled the teleportation function of Captain Jack's Time Agency wrist strap in DW: Last of the Time Lords and regained the correct digits to reactivate it in this episode.


 * Gwen states that she intends to "go out fighting" like Owen Harper and Toshiko Sato to Ianto after handing him a firearm during the Dalek invasion of Torchwood 3, referring to their deaths in TW: Exit Wounds.


 * The sub-wave network mentioned by Harriet Jones, and funded by the Mr Copper Foundation is most likely a reference to Mr Copper from DW: Voyage of the Damned.


 * The Doctor mentions a previous attempt to move the earth "a long time ago", possibly a reference to the goal of the Daleks in DW: The Dalek Invasion of Earth, as well as the feature film remake Daleks - Invasion Earth 2150 AD which co-starred Bernard Cribbins, who plays Donna's grandfather in this episode. It may also have been a reference to the moving of earth in The Mysterious Planet, when it became known as Ravolox. Both incidents, however, occur far into Earth's future.
 * Sarah Jane Smith, Rose, Jack, Martha have all encountered the Daleks.
 * Sarah first encountered the Daleks in DW: Death to the Daleks and then in Genesis of the Daleks where she also encountered Davros.
 * Rose first encountered the Daleks in DW: Dalek, and then in DW: Bad Wolf (TV story)/The Parting of the Ways and in DW: Army of Ghosts/Doomsday.
 * Jack previously encountered them in DW: Bad Wolf (TV story)/The Parting of the Ways although it is implied that he has encountered them before those episodes.
 * Martha first encountered the Daleks in DW: Daleks in Manhattan/Evolution of the Daleks.


 * Gwen does not know who the Daleks are; this is a reference back to an early episode of Torchwood in which it was stated that an attempt at covering up some elements of the Battle of Canary Wharf was made. Similarly, when Jack first contacts Martha, he references putting something in his drink, referencing the "contaminated water supply" cover story.
 * Donna is told that she had something on her back. She was first told she has something on her back in DW: The Fires of Pompeii and it was a major element of the preceding episode, Turn Left the Beetle sound effect is heard as this point as well.
 * This is the second on-screen appearance of the Judoon the first being DW: Smith and Jones. They also appear in TDA: Revenge of the Judoon.


 * The Daleks say "The Daleks are the masters of Earth!" they previously said this in DW: The Dalek Invasion of Earth.
 * The Doctor calls out "Bye!" to Davros in a similar fashion that the Fourth Doctor bade him farewell in DW: Destiny of the Daleks and the Seventh Doctor in DW: Remembrance of the Daleks. The Master also maks a similar call-out in Utopia whilst stealing the TARDIS.


 * Jack refers to Sarah Jane's encounters with the Slitheen (SJA: Revenge of the Slitheen) and (SJA: The Lost Boy).


 * The Doctor's TARDIS has reverted to its original appearance and is no longer covered with the words "Bad Wolf" as at the end of Turn Left.


 * Mr Smith using every phone on Earth to call The Doctor is similar to everyone saying 'Doctor' in Last of the Time Lords


 * The Doctor forces himself to stand in order to begin regeneration. This is consistent with the previously seen regenerations of the Ninth Doctor and The Master, but not of the regenerations shown for the the first eight Doctors, all of whom are shown regenerating lying down (save for the Second and Eighth Doctors whose regenerations are not shown). During most of the Doctor's regenerations he is rendered unconscious or severely weakened, which would make him incapable of standing. The enormous display of energy seen during his ninth and the Master's most recent regenerations could also be connected to their level of consciousness and strength.


 * In The Parting of the Ways the Emperor of the Daleks used the name 'The Abomination' on Rose and in this episode The Dalek Supreme used the same nickname for Dalek Caan. This is also the name given to the Special Weapons Dalek in the novelization of Remembrance of the Daleks (novelisation).