Planetary Relocation Incident

The 21st century Dalek invasion was a war fought between the New Dalek Empire and other races — mostly humans. It was fought in the Medusa Cascade in a pocket dimension that was put one second out of sync with the rest of the universe in 2009. (TV: The Stolen Earth) An online news article about Adelaide Brooke, posted on 22 November 2059, incorrectly dated the event as 2008. (TV: The Waters of Mars)

Background
In the first year of the Last Great Time War, Davros' command ship flew into the jaws of the Nightmare Child at the Gates of Elysium. He was rescued by Dalek Caan, the last survivor of the Cult of Skaro; after activating an emergency temporal shift, Caan entered the time-locked Time War - "flew into the wild and fire", as he put it - and rescued his creator. Caan lost his mind and gained psychic abilities following this event; it is unclear whether it was the act of breaking the time lock, or entering the War, that caused this.

Davros made Caan his prophet and set to work reviving the Dalek Empire of before the Time War. After building the Crucible, restoring the Dalek Fleet to two hundred ships and creating thousands of Daleks with the Kaled mutants inside grown from the cells of his own body, self-mutilating himself until his ribcage and vital organs were exposed, (TV: The Stolen Earth) Davros set to work creating a reality bomb. This superweapon was to destroy all of reality in every universe except the Crucible, leaving Daleks the only species in existence. (TV: Journey's End)

To power the reality bomb, twenty-six planets and one moon were stolen from times and places across the universe so their gravitational fields, once aligned, would act as a gigantic engine. (TV: The Stolen Earth / Journey's End) These included Earth, which brought the problem to the Tenth Doctor's attention. The Shadow Proclamation, after the Doctor's visit to them, wanted to go to war with the as yet unknown perpetrators of this event. However, the Doctor did not wish for a full-scale war and left for the Medusa Cascade. (TV: The Stolen Earth)

Invasion of Earth
Not long after the planets were brought into the Cascade, the Dalek Fleet attacked. Most of the efforts seemed to go to Earth. The Unified Intelligence Taskforce and the armies of Earth fought back, but were no match for the Dalek onslaught and were quickly slaughtered. The Valiant was destroyed almost immediately, the RAF retreated over North Africa, and military bases across the planet were attacked and personnel exterminated, although Martha Jones used Project Indigo to teleport away with an Osterhagen Key. Soon afterward, the Commander General of the United Nations surrendered Earth to the Daleks.

A subwave network, created by the Mr Copper Foundation and developed by Harriet Jones, former British Prime Minister, was used by Harriet to try to contact the Doctor. While the Daleks attacked Harriet's house, killing her, Harriet, Torchwood, Martha and Sarah Jane Smith (with the help of Mr Smith) transmitted a message to the Doctor, helping him find the location of the stolen Earth. The Daleks traced the signal and attacked Torchwood. (TV: The Stolen Earth)

The Doctor arrived as the Dalek assault continued. Thanks to a time lock in the Torchwood Hub, the Torchwood team survived the attack on them. Sarah Jane, trying to find the Doctor, was found by Daleks but saved by dimension-hopping Mickey Smith, Rose Tyler and Jackie Tyler. When Rose and the Doctor reunited, he was shot by a Dalek. Jack quickly teleported to them, destroying the Dalek. Jack, Donna and Rose then helped the Doctor back to the TARDIS and watched him prepare to regenerate. However, the Doctor managed to abort the process by channelling the energy into his severed hand. Although he did not change his face, it did use up one of his regenerations. (TV: The Time of the Doctor) They surrendered to the Daleks to find the Doctor, who had been taken prisoner with Donna Noble, Jack Harkness and Rose Tyler and taken to the Crucible. (TV: Journey's End)

Reality Bomb
The Daleks, using Davros' plans, had created a weapon called the reality bomb. Powered by the twenty-seven planets the Daleks had stolen, this ultimate weapon was capable of literally reducing the entire universe to nothing. They ran a test of the bomb on a small group of human prisoners, including Sarah Jane Smith, Mickey Smith and Jackie Tyler. Mickey and Sarah Jane escaped to a side chamber and Jackie teleported to it with her dimension jump just before the weapon was tested.

This saved them from being reduced to atoms. This terrible weapon would wipe out all life in every universe. In Pete's World, a universe which the Doctor said was further ahead in time than his, the reality bomb had already put out the stars. Meanwhile, the Daleks captured and tried to destroy the TARDIS with Donna Noble still inside. The regenerative energy in the Doctor's severed hand triggered a Meta-Crisis in conjunction with Donna Noble. A new version of the Tenth Doctor was produced. This Meta-Crisis Doctor and Donna escaped in the TARDIS, which everyone else thought destroyed in the Z-Neutrino core. They prepared to turn the reality bomb on the Daleks themselves.

Sarah Jane, Mickey, Jackie and Captain Jack threatened to detonate a warp star to destroy the Crucible if the Daleks did not back down and Martha Jones threatened to destroy the Earth with the Osterhagen Project to make the required twenty-seven planets twenty-six if the same thing wasn't done, but the Daleks teleported them all to the Vault and trapped them there with the Doctor and Rose. The Meta-Crisis Doctor and Donna arrived in the TARDIS to put their own plan into action, but were quickly stopped by Davros, who zapped them with his electricity-shooting prosthetic hand.

For a moment all seemed lost. However, the shock that Donna had received caused her Time Lord side to activate. She had become part-Time Lord when the Meta-Crisis Doctor was created, causing her to gain the Doctor's intelligence. She manually deactivated the reality bomb by closing off all of the Z-Neutrino energy relay loops using an internalised synchronous back-feed reversal loop, disabled the Daleks' weapons and systems by locking their weaponry in a self-replicating energy blindfold matrix through macrotransmission of a K-filter wavelength and creating a trip stitch circuit-breaker in the psycho-kinetic threshold manipulator. She also released the others from their cells. (TV: Journey's End)

Destruction of the Crucible
With the reality bomb disabled and Dalek controls malfunctioning, the Doctor's companions got rid of all of the Daleks in the Crucible. Mickey held off Davros with Rose's gun. The two Doctors and Donna started returning all twenty-seven planets to where they belonged, but the Supreme Dalek descended to the Vault and attacked, disabling the machinery before Jack killed him. All of the planets but Earth had been returned, but the Doctor readied the TARDIS to tow it back. The Doctors also realised that Dalek Caan had been manipulating everything to lead to the end of the Daleks. With his warped mind no longer truly Dalek, he had realised how evil they were. Goaded by Dalek Caan and knowing the Daleks had sufficient numbers to take the universe by force without the reality bomb, the Meta-Crisis Doctor used the control panel to overload all of the Daleks' Dalekanium and blast it back, destroying the Daleks and their ships and blowing up the Crucible.

The two Doctors and their companions escaped in the TARDIS. Although the Doctor offered, Davros refused to come with them and suffered an unknown fate when the Crucible blew up, along with Dalek Caan. With the help of Mr Smith, K9, Ianto and Gwen, the Doctor towed the Earth back to where it belonged with Sarah Jane, Mickey, Rose, Martha and Jack acting as co-pilots in the TARDIS. (TV: Journey's End) Unknown to them, a Dalek flying saucer and its crew of three Daleks (TV: Victory of the Daleks) survived the fall of the New Empire, (PROSE: Dalek: The Astounding Untold History of the Greatest Enemies of the Universe) once again giving the Daleks the chance to rebuild. (TV: Victory of the Daleks)

The reality bomb and the Void
The effects of the reality bomb broke down the Void, destroying the millions of Daleks and Cybermen that were previously trapped there in the Battle of Canary Wharf. However, a small portion of Cybermen fell to Victorian era London around December 1851. They were later stopped by the Tenth Doctor, who sent them into the time vortex, where they disintegrated. (TV: The Next Doctor) More groups of Cybermen, however, also apparently managed to escape the Void before being destroyed and went on to develop space travel, allowing them to begin expanding again. Most of the Cybermen, however, perished. (TV: The Pandorica Opens, GAME: Return to Earth) In Pete's World, as the reality bomb was stopped, dimensional retroclosure restored the damage and sealed the Void again. (TV: Journey's End)

Effect on Earth
Trinity Wells reported on the Earth being stolen. (AUDIO: Driving Miss Wells) Shortly after the invasion, by September 2009, at least half of Earth accepted the existence of alien life, while the other half were in denial. The events, combined with other invasions, led to an increase in suicide from crises of faith. Prime Minister Brian Green was left fatalistic by the invasion. (TV: Children of Earth: Day One)

The events of this invasion were recounted in Daleks - Invasion Earth, by Christian Peterson. (PROSE: The Secret Lives of Monsters)

When Clyde Langer admitted to his father that he fought aliens, Paul used the Daleks as a frame of reference. (TV: The Mark of the Berserker)

Adelaide Brooke, commander of the first mission to colonise Mars in the 2050s, was a little girl at the time of the attack on Earth. Both her parents were lost and presumed killed. Her father's last words to her were to stay inside. She did, but a hovering Dalek approached her house. It saw Adelaide, but, apparently realising she was a fixed point in time, did not exterminate her. This encounter with an alien inspired her to explore in space. According to the Tenth Doctor, Brooke's exploration of Mars, destined to end with her death, not only inspired generations of her family to reach beyond Earth, but also had a major impact on the human race leaving the confines of Earth. (TV: The Waters of Mars)

The Eleventh Doctor said that it would be impossible for anyone from 2009 not to recognise a Dalek. He realised something was wrong with Amy Pond's memories/timeline when she didn't recognise the Daleks. (TV: Victory of the Daleks)

The Doctor and his companions
Due to the creation of his half-human clone, this left the Doctor with one final regeneration in his first cycle. (TV: The Time of the Doctor) This event caused the Doctor to lose all of his companions: Martha and Jack returned to their normal lives with Mickey joining them as he no longer had anything to tie him to Pete's World. Sarah Jane also returned to her family, the Doctor returned Jackie to Pete's World where he left Rose against her wishes, but left the Meta-Crisis Doctor with her who, due to being half-human, would be able to live a normal life with her. However, while Donna was willing to stay with him, having a Time Lord mind overwhelmed her and the Doctor was forced to erase all knowledge of his existence from her mind and return her to her family. (TV: Journey's End) As a result, the Doctor originally chose not to have any permanent companions anymore, but then later ignored this, taking on Heather McCrimmon, Gabby Gonzalez and Cindy Wu and, after his regeneration into the Eleventh Doctor, Amy Pond. (TV: Planet of the Dead, The Eleventh Hour, COMIC: The Chromosome Connection, The Arts in Space, Arena of Fear)

State in the timeline
Despite the impact the invasion had on the people of Earth, the Eleventh Doctor discovered that his companion, Amy Pond, despite being from 2010, knew nothing of it. (TV: Victory of the Daleks) The Twelfth Doctor's companion Bill Potts, who was from the year 2017, (TV: Knock Knock) was also unaware of what Daleks were. (TV: The Pilot) The Doctor later linked this to the nature of the time field, a form of crack or entity that had erased people and events like this from history by unwriting their/its existence. When the cracks erased an event from history, the change to history was usually minor. In some cases, the consequences of the event still remained. (TV: Flesh and Stone) The Big Bang Two restored some individuals unwritten by the cracks, like Amy's mum and dad, but the status of this event was not addressed. (TV: The Big Bang)

The Doctor, the Daleks, (TV: Victory of the Daleks) and Davros all remembered the invasion. (TV: The Magician's Apprentice) Although the memories of the invasion remained suppressed until the Twelfth Doctor and Clara Oswald reopened them, Rusty the Dalek still knew of the invasion. (TV: Into the Dalek) Davros also had footage of the Doctor during the invasion. (TV: The Magician's Apprentice)

The Thirteenth Doctor's friends Graham and Grace O'Brien, Ryan Sinclair and Yasmin Khan as well as Karl Wright were apparently some of those affected by the cracks' memory-erasure, despite being from 2018, as they didn't know about aliens. (TV: The Woman Who Fell to Earth) Graham, Ryan and Yaz likewise were surprised when the Doctor told them about her towing Earth back in place. (TV: The Battle of Ranskoor Av Kolos) They also didn't recognise the shape of the Dalek recon scout. (TV: Resolution) Jack Robertson, who did not recognise the word "Dalek," and the citizens of the United Kingdom were not familiar with the design of the Defence Drones. (TV: Revolution of the Daleks)

However, a book chronicling the history of N-Space knew of the invasion and recounted it. (PROSE: The Whoniverse) Additionally, Justin Richards, a 21st century alientologist who wrote The Secret Lives of Monsters, knew of the invasion, Battle of Canary Wharf, and other events, which pushed him to write the book. He further claimed no one could ever forget the 2009 Dalek occupation and that everyone on Earth knew what they looked like. He explained that "the rest of the world" had moved on from the invasion, though he also claimed that millions were forever scarred. Richards also wrote that people had terrifying memories of the occupation and that there was an ever-present fear that the Daleks would return. (PROSE: The Secret Lives of Monsters) Indeed, the Daleks did again attack 21st century Earth, as a force of Death Squad Daleks attacked in 2021 but engaged in a civil war against the Defense Drones. The Death Squad Daleks had also known to expect resistance from 21st century Earth. (TV: Revolution of the Daleks)

Behind the scenes
According to The Dalek Handbook, the three Daleks which created and were subsequently destroyed by the New Dalek Paradigm in Victory of the Daleks were survivors of the 2009 Dalek invasion of Earth. An in-universe book, Dalek: The Astounding Untold History of the Greatest Enemies of the Universe, later confirmed this was the case.

Special Daleks, a 1994 short story in DWPM 1, was the first source to mention a 21st century Dalek invasion of Earth, though Marcus Hearn had no way of knowing, at the time, that such an event would actually be depicted on television a decade later — nor does it seem likely that Russell T Davies intentionally referenced Special Daleks in plotting out the Series 4 finale. All the same, Hearn correctly predicted that the invasion would be overseen by a Supreme Dalek.