User:Bongolium500/Sandbox 15

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To use it, click the text bellow corresponding to the various types of sources. As this is in an early stage, there aren't many options on what to hide. In future, this could be expanded to allow the hiding of individual series, etc.

As Missy
After returning to his TARDIS, the Master regenerated into a new incarnation (PROSE: Girl Power!) the same incarnation that had fatally wounded him, (TV: The Doctor Falls) and who referred to herself, in a list of her incarnations, as "the Best One". (PROSE: Meet Missy!)

Due to the presence of her older self during the events surrounding his regeneration, she was left unable to recall the exact specifics of it due to their timelines being out of sync, (TV: The Doctor Falls) recalling only that she woke up in a female body, (AUDIO: The Bekdel Test) and also lost all knowledge of her former time on the Mondasian colony ship, (TV: World Enough and Time) save only that a "very scary lady" had advised to always carry a spare dematerialisation circuit. (TV: The Doctor Falls)

Early endeavours
As with her previous incarnations, the Master went to the Scoundrels Club to recover from the regeneration. After she was ousted from the Club by Harrison Mandeville for being a woman, the Master went on to systematically kill specific members for her revenge, and recruited an 18th century slave at the Mandeville sugar plantation named Saffron, whom coined the name "Missy" for the Master's current incarnation.

While Saffron infiltrated the Club through the kitchens, (PROSE: Dismemberment) Missy was brought to the Bekdel Institute, where she encountered River Song. After Missy taunted her, and killed a few of the other prisoners, River realised she could help her escape. To throw off the Director, she created two sets of solidograms, similar to him, one to be placed in the detention cells, while the other set to be caught in the sewers. It was around this time they figured out that the prisoners were in fact solidograms, generated by the main computer. While Missy and River meddled with the systems, they figured out that they were brought to the prison to check if the Eleventh Doctor was really dead after his assassination. They finally escaped after Missy tricked the computer into thinking that the inside was the outside and vice versa. Missy and River were transported to a planet, where Missy got back to her TARDIS. She told River that she knew something about her future, but that she couldn't tell. Missy also explained that she couldn't kill River because she was a complicated space-time event. Missy then teleported River back to Stormcage, just for the fun of it. (AUDIO: The Bekdel Test)

While searching for a replacement power source for her TARDIS's Eye of Harmony, Missy was forced into working for the High Council by the General, with Yayani being assigned her "companion" in her mission to investigate time experiments at the Kyme Institute. At the Kyme Institute, Missy and Yayani found that Doctor Kalub was keeping a pregnant creature confined in a bubble of time energy, constantly shifting between life and death. Having paralysed Kalub with her sonic umbrella, Missy goaded Yayani into killing him, and then killed Yayani with the Tissue Compression Eliminator, sending her remains back to the General with a warning not to bother her again, as she had jettisoned her Eye of Harmony, replacing it with Kalub's creature. (PROSE: Lords and Masters)

Shenanigans with the Master TARDIS
Missy was captured by the Wardens, who punished her for a crime she had yet to commit. Under the supervision of Mr Cosmo, she was exiled to 19th Century London and forbidden from harming anyone or using anachronistic technology. Following Cosmo's suggestion to get a job, Missy took a role as the governess of Oliver and Lucy Davis. Under the guise of field trips with the children, she investigated places of old power, awakening a Sphinx and stealing an ancient genie from the British Museum. Lucy became suspicious of her, but Oliver remained enthralled and helped Missy gain access to the opening of the Circle Line which their father had been working on. Missy used the circular shape and terror of the passengers on the out of control train, being accelerated by the genie, to charge up a ruby from the Sphinx with ancient power. She then turned on the children, attracting Cosmo's attention. The ruby interfered with his transmat, transporting him into the genie's vase. Stripped of his power, Cosmo was unable to stop Missy using her vortex manipulator to escape. (AUDIO: A Spoonful of Mayhem)

Plotting to obtain control of the Master TARDIS, Missy sought the necessary components to reactivate it. (AUDIO: The Belly of the Beast) She travelled to 15th Century England to find a time traveller who was causing distortions by posing as Henry VIII, discovering they were actually the Monk, who had hidden from the Time War there and was now creating distortions in hopes of attracting the Time Lords' attention for rescue. Her plans were thrown into chaos by the arrival of the Gramoryans, who had been attracted by the Monk's meddling. She was forced to expose the Monk as an impostor to divert them, by revealing the real Henry. She and the Monk were sentenced to execution for treason, however she managed to hypnotise the executioner and they retreated back to the Monk's TARDIS. There Missy stole the component she needed and escaped by vortex manipulator, leaving the stranded Monk swearing vengeance against her. (AUDIO: Divorced, Beheaded, Regenerated) Missy then tracked down her Time War TARDIS, which had hidden from her in 2014 Manhattan. She accompanied Dick Zodiac in his investigation of deaths where the victims had seemingly aged to death. Dick found her TARDIS, which was traumatised from the War and now communicating by an avatar called Mark. Mark let her and Dick in, however a future version of Dick who had been relieving the events in simulations intervened and revealed her true identity to Mark, giving young Dick her vortex manipulator. Refusing to be her tool again, the TARDIS attempted to throw itself into a sun but Missy found the factory reset and regained control. (AUDIO: The Broken Clock) Locating the Master TARDIS in the belly of a dead space creature, Missy used processed clones as a slave army to excavate it. Growing bored, Missy and her own future self played a game where the future Missy attempted to cause a rebellion, to keep her occupied. When the TARDIS was found, Missy used a vortex manipulator to travel back in time to be the rebel leader whilst the older Missy claimed the TARDIS. She used the Monk's component to open its Eye of Harmony and threw her old TARDIS into it as fuel, activating the Master TARDIS. (AUDIO: The Belly of the Beast)

Finding the Master TARDIS wasn't working properly, Missy embarked on a series of plots to attract the Doctor's attention, including kidnapping Bertram to be her companion. Instead she attracted the attention of the Lumiat, who she initially mistook for the Doctor. Eventually the Lumiat revealed her true identity as Missy's next incarnation, a distillation of goodness created by an Elysian field. Missy and the Lumiat went on a series of adventures together, during which Missy killed Bertram out of boredom. After Missy threatened to destroy a rare egg that was causing a truce in a civil war, the Lumiat snapped and threatened to kill her with her TCE. She missed and Missy shot her whilst throwing her the egg, smashing it and mortally wounding the Lumiat. Having grown bored of her, Missy dumped the Lumiat on a random planet mid-regeneration. (AUDIO: The Lumiat)

Still wanting the Doctor's attention, Missy went to Earth and took over a boarding school in Scotland. Oliver Davis arrived at the school and managed to send word to his sister, who arrived with Strax. Fending off their interference, Missy decided to have the boys dig up an ancient mound in search of ancient power. However she was foiled by the arrival of Cosmo, who had been freed by Strax's comrades on the Davis' instruction. Missy escaped by vortex manipulator, (AUDIO: Brimstone and Terror) to 1605, however it was drained of power. Missy decided to meddle in the Gunpowder Plot to attract the attention of a time traveller and came into conflict with a rookie Time Agent. However Missy's meddling was undone and she was captured by the culprit - the Monk. (AUDIO: Treason and Plot) Before the Monk could exact his revenge, they were captured by the Ogrons who were seeking payment from the Master, and assumed the Monk was him. Missy eventually helped the Monk escaped, however revealed she'd programmed his TARDIS to only operate with both of them aboard. As he despaired, she proclaimed this to be the beginning of a "horrible friendship". (AUDIO: Too Many Masters)

Reclaiming her friend
Missy decided to manoeuvre Clara Oswald into becoming the Doctor's companion, believing that Clara was just the right companion to attract the Doctor's interest and make it easier for Missy to emotionally manipulate him, (TV: Death in Heaven) showing him "the friend inside the enemy, [and] the enemy inside the friend." (TV: The Witch's Familiar) Ashildr believed that Missy placed the two together so that that the Doctor and Clara in tandem would become the Hybrid of Gallifreyan myth. (TV: Hell Bent) In 2013, Missy gave Clara the Doctor's phone number, claiming that it was a tech support line, leading Clara to meet the Eleventh Doctor. (TV: The Bells of Saint John, Death in Heaven) She then kept the Doctor and Clara together into the Doctor's twelfth incarnation by placing an ad in a newspaper for Mancini's Family Restaurant. (TV: Deep Breath, Death in Heaven)

After killing Clara's boyfriend, Danny Pink, by running him over with a milk float, Missy returned to the Scoundrels Club to finalise her revenge by having Saffron poison the last remaining members with a temporary paralysing agent. After stranding the majority of the members in the past to act as slave labour, Missy taunted Mandeville a final time by permanently paralysing him and propping him up as furniture, while she made plans for Dr Skarosa. (PROSE: Dismemberment)

To create a new army of the Cybermen, (TV: Dark Water) whom she called her "Cyberdears", (PROSE: Meet Missy!) Missy founded the 3W Institute, in order to create a Cyberman army of the dead. (TV: Dark Water) Needing to collect matrix slices that she had acquired in her previous incarnation, Missy travelled to London to meet her former wife, Lucy Saxon, who had been sent to sell three matrix data slices to another incarnation of the Master. Missy spoke to Lucy about her husband and told her that one day she would have to kill him with a gun. Lucy listened to her story about what would happen to her, and how it would all work out, though she did not tell Lucy that these events would also result in her death. Lucy agreed to the terms and gave Missy the three matrix slices. (PROSE: The Unwanted Gift of Prophecy) Missy used the matrix data slices to create the Nethersphere, where she uploaded dying minds to. This reality changed and rewrote the minds, removing their emotions before re-downloading them into their Cyber-converted bodies. (TV: Dark Water)

Missy went along the Doctor's timeline and greeted people who died in connection with him, (TV: Death in Heaven) such as the Half-Face Man (TV: Deep Breath) and Gretchen Carlisle. (TV: Into the Dalek) Finding this made her "a bit busy", (TV: The Caretaker) Missy began to secretly monitor the Twelfth Doctor and Clara, (TV: Flatline) as she did when Earth was saved from a solar flare by a forest that grew overnight. (TV: In the Forest of the Night)

Missy finally met the Twelfth Doctor and Clara at one of 3W's mausoleums, which was hidden inside St Paul's Cathedral (TV: Dark Water) with dimensional engineering. (TV: Death in Heaven) Initially posing as an android, Missy revealed her true identity to him as the Cybermen marched out onto the streets of London. (TV: Dark Water) Missy was quickly captured by UNIT, having anonymously tipped them off on the Cybermen's presence. She watched as Cybermen flew into the sky and exploded above major population centres, creating clouds that rained Cyber-pollen, turning the dead into Cybermen. Taken onto Boat One along with the Doctor, she sent out a signal to the Cybermen, to attack the plane before freeing herself, (TV: Death in Heaven) and disintegrating the Zygon Osgood. (AUDIO: Narcissus) Missy then ordered the Cybermen to remove a piece of the fuselage, causing Kate Stewart and the Doctor to be sucked out before ordering the Cybermen to destroy the plane, and teleporting away. In the Nethersphere, Missy and Seb watched the Doctor free falling and saving himself by using his key to summon the TARDIS. When Seb got overexcited at this dramatic turn of events, Missy casually disintegrated him.

After the Doctor found out from the Cyber-converted Danny Pink that she planned to have the Cyber-pollen fall again so that humanity would be reborn as Cybermen, Missy then arrived to give the Doctor control of the Cybermen, wanting him to use them as his army, in the hopes of proving the similarities between them. However, after pondering the idea, the Doctor proclaimed himself to be simply an "idiot with a box" rather than a general or any sort of leader. He turned control over to Danny, who ordered the army into the sky to destroy themselves, dispersing the threatening rain clouds.

After the threat of the Cybermen had ended, Missy gave the Doctor coordinates to the current location of Gallifrey, lying to the Doctor that the planet had returned to its original location and that she and the Doctor could travel there together. However, Clara, using Missy's own weapon, decided to kill her. The Doctor wouldn't let Clara kill Missy, and decided to kill his old friend himself to "save [Clara's] soul". Before he could fire the weapon, however, Missy was shot by the late Brigadier Lethbridge-Stewart, who had been resurrected by the Cyber-pollen, (TV: Death in Heaven) but Missy used the energy from the blaster to recharge her vortex manipulator and escape undetected. (TV: The Witch's Familiar)

Further schemes
Despite the Celestial Intervention Agency protocols attempting to stop her, Missy was able to hack and corrupt her file in the TARDIS databanks, adding in mocking remarks and ending with a veiled promise to kill whoever viewed the video file. (WC: Who Is The Master?)

Enslaving a reality changing bear by the name of Teddy Sparkles, Missy arranged for herself to become governess at Queen Square, and used the innocence of the children to manipulate them and Teddy Sparkles into wishing for a future where they became influential entrepreneurs. When the time was right, Missy tried to threaten the children, having grown up to be very well connected, into handing her the means to dominate the Earth, but Teddy Sparkles was able to reverse the timeline to stop Missy, though he had to sacrifice his life to completely to fix the timeline afterwards. However, he was able to change reality enough to have Missy known throughout the world of 1925 as the nicest governess of all time, forcing her to leave in humiliation. (PROSE: Teddy Sparkles Must Die!)

Missy went to face the tests to gain the power of Iarbus, but the wizard refused because she was a woman and drained her life essence into her power source. Missy was able to resist destruction and keep her identity, and used the power to send mental messages to five of the most evil and cruel conquerors in the universe. She didn't mind-secure them, though, and because of that, Daphne Nollis, housekeeper to one of the five warlords summoned, was instead brought there in his place. Missy led the men through Iarbus' trials, which only Daphne and another man, Dib the Magnificent, survived. When Iarbus came to give the winner his prize, Missy used the power of the source to regain physical form and killed Iarbus and Dib by absorbing them into the power. As she was gloating for her victory, Daphne took advantage and grabbed the power for herself, snatching it from Missy's hands. Realising Daphne had become too powerful for her to defeat, Missy withdrew. (PROSE: Missy's Magical Mystery Mission)

Trapped on Skaro
After she was given the Doctor's confession dial from Ohila, Missy tried to find the Doctor to get answers, but was unable to locate him. Needing assistance, Missy got the attention of both Clara and UNIT by freezing all the airborne planes on Earth in time. Managing to arrange a treaty with Clara, Missy helped UNIT deduce that the Doctor was hiding in 1138 Essex, and used her vortex manipulator to transfer herself and Clara to the location, where the Doctor was throwing a party.

When Colony Sarff arrived to capture the Doctor, having been led there by following Missy and Clara, Clara volunteered herself and Missy as prisoners, and were taken to Skaro. While the Doctor was taken to Davros, Missy and Clara escaped their cell, but were soon captured by a Dalek. They were taken to the other Daleks and seemingly exterminated. (TV: The Magician's Apprentice) However, Missy and Clara had survived by using the Dalek blasts to recharge Missy's vortex manipulator and the one she gave Clara, and teleporting from the Dalek city, burning them out in the process.

Missy and Clara entered the Dalek sewers, composed of rotting Daleks, with Missy using Clara to lure a Dalek there. She cut through its case using her dwarf star alloy brooch, enabling the rotting Daleks to kill it. She put Clara inside the case and pretended to be her prisoner, enabling her to re-enter the Dalek control room and propose an alliance with them. When the Daleks began to gain Time Lord regeneration energy, Missy used their incapacitation to find the Doctor. She used a Dalek gun to shoot Colony Sarff, saving the Doctor. She then watched as the Doctor toyed with Davros about the revived Daleks in the sewers and even tapped Davros' Dalek eye as they made their escape.

With the city being destroyed by the regenerated sewer Daleks, Missy tried to trick the Doctor into killing Clara inside the Dalek. However, the Doctor realised the deception and told Missy to run. Trying to escape, she was surrounded by Daleks when the city crumbled in on itself, but purported that she had "a really clever idea". (TV: The Witch's Familiar) Missy spent some time on Skaro, even adopting a Slyther, which she named "Doctor," and writing a postcard to the Doctor, promising she would see him soon. (PROSE: Postcards from the Universe) One Gallifreyan believed that, after she escaped the Daleks on Skaro, Missy went back to Gallifrey and told Rassilon that the Doctor knew about the Hybrid. (PROSE: A Brief History of Time Lords)

After Skaro
After eluding the Daleks, Missy was forced into the Time Vortex, where her TARDIS collided with a Gryphon time ship. Caught in a temporal embrace, the Gryphons attacked Missy's TARDIS, and Missy was forced to land in St Mark's Square in Venice. With her dematerialisation circuit damaged from the attack, Missy walked through the market to get her bearings, and had the circuit stolen by pickpockets Mario and Antonia. Pursuing Mario, Missy saw him being absorbed by a temporal shift with her circuit, and later found it in a museum.

Knowing she would need to venture into the temporal shift to retrieve her circuit, Missy met with a local museum curator to find out where the circuit was located, and then travelled through the temporal shift to 14th century Venice with Antonia, where they found the Gryphons attacking. Separating from Antonia, Missy found Mario's deceased body and retrieved her dematerialisation circuit. Telling Antonia that Mario had been sent back, Missy and Antonia returned to modern Venice, where Missy reverted the damages of the temporal shift by flooding Venice. (PROSE: The Liar, the Glitch and the War Zone)

Hearing that the Doctor and Clara had been forced to enter Battle of the Bands Beyond the Stars, Missy came up with a new plan for universal domination. Travelling through her time stream, she recruited her, Tremas,  Bruce and , and formed a band to compete on the show. The group planned to use the popularity of the program to hypnotise the audiences across the galaxy. According to Missy, the five spent "decades" preparing for the performance. (COMIC: The Five Masters)

The group went on before Clara and the Doctor due to a shift in the program's schedule, and the five revealed themselves to the pair. (COMIC: The Abominable Showmen) Missy expected the Doctor to attempt to stop the five of them, or to at least inquire on their plans, but the Doctor refused to intervene or question their scheme. After much prying, the Doctor correctly predicted the group's plan, but still refused to intervene as they started their song. As she prepared to hypnotise her audience, her previous incarnations began to fight with her over her device, as each wanted to control the universe without the others. During the fight, viewers began to turn off their sets and the group were soon all disqualified and were thus blown up, although neither Clara nor the Doctor believed that they had truly been killed. (COMIC: The Five Masters)

Missy became a headteacher for the school Saxon Heights after she had done away with the previous one. She implemented new and strange rules, such as a school uniform that was almost identical to her own clothing, and getting rid of everyone's mobile communication devices, with her excuse being that they were used too often. However, the real reason was because that she wanted to summon a Dæmon by hooking up her newly acquired devices to a transmitter. The Osgoods found this out and had UNIT stop her, although Missy managed to escape. (PROSE: Yes, Missy)

Missy goaded the Doctor into following her through various time periods while she stole valuable items. The Doctor was too late to stop her each time. Finally catching up with her in the Stone Age, the Doctor revealed to her that he had discovered her true plan: to leave Cybermats behind where she stole each item. Missy expressed her desire to further reveal her plan to him. The Doctor instead refused to listen and boarded the TARDIS in search of some lunch. (PROSE: Dr. Twelfth)

In 1963, Missy filled in as Coal Hill School's supply room teacher. She added a ladder to the supply room which allowed the First Doctor and Shivani Bajwa to escape a pack of alien wolves. Shivani later described the incident to Missy and thanked her for the ladder. (PROSE: Doctor Who and the Horror of Coal Hill)

Responding to a distress call from her secret base, Missy found that had had his TARDIS stolen by Liv Chenka. Working with her "War" and their in a plan to use the Crucible of Souls to counter the plot of the Ravenous, Missy kidnapped Helen Sinclair to translate the Prophecy of Artron in the future of Earth. After taunting Helen in Artron's tower, Missy took Artron back to the "War" Master, and broadcasted a message to the Eleven for him to return to the Crucible, planning to use Artron as a bargaining chip.

With the Eleven distracted by the Eighth Doctor, Missy helped to remove the regeneration ability from the citizens of the universe, and called in the fleet of Battle TARDISes in orbit around the Crucible to destroy it. Escaping in the "War" Master's TARDIS, Missy joined her past incarnations in shooting the Eleven and left her vortex manipulator with the Twelve. Although the Time Lords requested Artron's Matrix print to give them the ability to grant new regeneration cycles to Time Lords, the Masters first used it to restore a past version of themselves to life with a new regeneration cycle. (AUDIO: Day of the Master)

Trial and execution
After she was captured by an unnamed species on an unnamed planet, (TV: Extremis) Missy was put on trial for her "crimes against the universe throughout all [her] lives". However, she talked her way out of being sentenced for the events of The Year That Never Was by pointing out the Tenth Doctor's undoing of those events, and for the murder of Petronella Osgood by pointing out that two Osgoods were still working for UNIT. She then pointed out she had already been punished for her actions at Devil's End, and cleared up confusion about her involvement in the Death Zone by reminding everyone that Borusa was the culprit on that occasion. She was, however, eventually sentenced to death for pushing a girl into a volcano on Riga-Priam. (PROSE: Missy on Trial)

In accordance with their Fatality Index, the Doctor was chosen to carry out Missy's sentence. However, he sabotaged the execution machine so that she was knocked unconscious instead of being killed. After swearing an oath to guard Missy's "body" for a thousand years, the Doctor scared the executioners away and had Nardole place her inside a Quantum Fold Chamber. (TV: Extremis) The Doctor and Nardole transported the vault to St Luke's University, where they continued to guard it for several decades. (TV: The Pilot) Missy would occasionally ask Nardole to order items for her, and the Doctor would have to approve her requests. (PROSE: Girl Power!)

Imprisoned in the Vault
While inside the Vault, Missy began reading up on how women were treated by history, and decided to help inspire a select group of women to rise against their male oppressors with a Spacebook group chat. However, the Doctor, thinking Missy was plotting an elaborate escape by messing with history, infiltrated the chat with the username "Circe" and dismantled Missy's leadership of the women. Missy then swore off ever trying to help the human race, and instead began a new campaign for the rats of Earth. (PROSE: Girl Power!)

In 2017, (TV: Knock Knock) after the Doctor began travelling with Bill Potts, (TV: The Pilot) Missy began banging on the doors of the vault, only for Nardole to assert that he would stand guard and prevent her escape. (TV: Thin Ice) When he later double-checked the locks, she started playing Für Elise on a piano the Doctor had given her. Once Nardole was dismissed by the Doctor, Missy started playing Pop Goes The Weasel when the Doctor told her about his adventure at 11 Cardinal Road. (TV: Knock Knock)

After he received an email from a simulation of himself warning of an upcoming invasion, the Doctor became tempted to release Missy from the vault. (TV: Extremis) When the Monks later occupied the Earth, the Doctor was kept prisoner for six months. After Bill helped him escape, he decided to consult Missy on how to defeat the Monks. Missy revealed she had dealt with them before, and that the only way to weaken their grip on power was to kill the psychic lynchpin being beamed to the whole planet. After the Monks had been driven off-world, the Doctor visited Missy in the vault again. This time, she claimed to be in deep regret of all the people she had killed throughout her lifetimes. The Doctor assured her she was making good progress on her redemption. (TV: The Lie of the Land)

Nardole later released Missy from the vault so that she could help him return the TARDIS to 1881 Mars after it unexpectedly departed and Nardole couldn't get it to return. After the Doctor and Bill entered the TARDIS, the Doctor was shocked to see Missy at the controls and reminded her that it was against their agreement and that he would have to return Missy to the Vault. To the Doctor's surprise, Missy easily agreed to return, and even questioned if he was alright with obvious concern. (TV: Empress of Mars)

Final endeavours
Deciding Missy was worth trusting, the Doctor released her from the Vault to perform maintenance work on the TARDIS while he took Bill and Nardole to find the lost Roman legion. Missy finished the work, and then took to watching the Doctor until he returned some days later. Nardole was frustrated that the Doctor had freed her, but he brushed him off, preferring to see if Missy had learned anything. Missy later cried as the Doctor watched on, both wondering if it was possible for them to be friends again and whether Missy was finally becoming the person the Doctor had desired to make her. (TV: The Eaters of Light)

The Mondasian colony ship
To test Missy's goodness, the Doctor recruited Bill and Nardole to be her "companions" and followed a distress call to a colony ship while the Doctor monitored Missy's progress from the TARDIS. However, Missy was ill-prepared to handle a frightened crewmember, Jorj, who subsequently shot Bill; she was carried off by passengers from Floor 1056. Missy accompanied the Doctor and Nardole in the lift to Floor 1056, (TV: World Enough and Time) where a time portal appeared. A humanoid hand reached out of the portal, and a voice asked to "grab on", before it disappeared. (COMIC: The Road To...) After reaching Floor 1056, the Doctor left Missy in charge of gleaning information from the computers. She discovered that the colony ship originated from Mondas while being pestered by a man called "Razor", who, upon confrontation, revealed himself to be, who Missy appeared to join forces with for the "Genesis of the Cybermen". (TV: World Enough and Time)

However, when the Cybermen turned on them, Missy knocked the Master down and claimed to have been playing him while still on the Doctor's side, but then admitted to being unsure of her allegiance. Just as Nardole arrived with a stolen shuttlecraft, the Doctor was attacked by one of the Cybermen. Missy entered the shuttle after the Master, as her younger self attempted to convince Nardole to leave without him. However, their shuttle was stopped by the Cyber-converted Bill, who still retained her humanity. Crashing through the floors, the shuttlecraft gave out at one of the solar farms on Floor 0507. (TV: The Doctor Falls)

That night, while the Doctor recovered from their escape, Missy accompanied the Master in venturing to Floor 0508 to revert the Doctor's edits to the Cybermen back on Floor 1056 and regain control of the Cybermen, though they were followed by Alit and a patient that Missy named "Topknot". However, after an encounter with a patrol of CyberNeomorphs, Missy prevented them from attacking Floor 0507 with a swarm of Cybermats, before rescuing her previous self with Alit and assisting the Master in destroying the Cyberman patrol; the two Masters then returned to Floor 0507 and abandoned their plans to control the Cybermen. On their journey back to the farmhouse, Missy, still conflicted over whether to side with the Doctor or her previous self, hypothesised that the only way to finish her internal conflict would be to kill the Master. (PROSE: Alit in Underland)

After two weeks of searching, the Master and Missy found disguised lifts, but Missy accidentally summoned the Cybermen in her attempt to escape. Unable to return to the Doctor's TARDIS due to how quickly time was moving on the floor of the Cybermen, the Doctor insisted that they had to prepare for a confrontation.

As the Doctor prepared to fight, the Master explained to Missy how he had blown the dematerialisation circuit in his TARDIS, which was surrounded by Cybermen on the bottom floor. Missy, recalling an instance where a very scary woman had pushed him up against a wall and insisted that he always keep a spare dematerialisation circuit, pushed the Master against the wall and insisted that he always keep a spare dematerialisation circuit, revealing the spare dematerialisation circuit she kept on her person. Before departing, however, the pair asked what the Doctor's plan was, knowing that he wouldn't be able to save everyone on the ship. As the Doctor explained that he wanted to save these people simply because it was the right thing to do and then implored the Master to stand with him, something the Master rejected, but Missy, speaking with the Doctor in private, admitted that she too wanted to stand with the Doctor as an ally, but still left with the Master. (TV: The Doctor Falls)

Death
As they prepared to depart, Missy offered to hug the Master and, after stating her enjoyment for being him, she stabbed the Master in the back, mortally wounding him in order to force his regeneration into her, but made the wound precise so that he would have time to reach his TARDIS before the regeneration occurred. Missy then helped the Master into the lift, explaining that she planned to stand with the Doctor and that it was the inevitable end that they had been leading towards their entire lives. However, the Master, declaring that he would never stand with the Doctor, shot Missy in the back with his laser screwdriver at full blast, claiming that he was mortally wounding her beyond the point of regeneration. With both of them laughing, the Master declared that their perfect ending was always going to be "shoot[ing] [them]selves in the back." As the Master departed for his TARDIS, Missy collapsed to the ground and seemingly died, (TV: The Doctor Falls) but she managed to regenerate into a new incarnation by creating an Elysian field to "kick start a new regeneration cycle". The process of cryogenetic extraction destroyed her body but retained a copy of her consciousness before regeneration. (AUDIO: The Lumiat)