Over Doctor Who's long history, there have been thirteen main incarnations of the titular character, as well as other hidden and alternate regenerations. Although The Doctor has fought the Daleks many times over the years and has had close friendships with many of their companions, their most important relationship is arguably with The Master.
Just like The Doctor, The Master has had several different incarnations over the years. While the two Time Lords have always had a complex relationship, the Missy incarnation of The Master shows a real evolution of the character and a potential change in this bond between the childhood friends-come-enemies. During her appearances, Missy has proved to be the best incarnation of The Master.
Missy's Elaborate Plans
What has always set The Master apart from many other Doctor Who villains is the elaborate nature of their schemes and Missy is no different in this respect. Throughout season 8, Missy welcomes different characters to what appears to be Heaven. In the season finale, Missy aligns herself with The Cybermen and aids them in converting the dead.
While almost every incarnation of The Master is over the top and elaborate in their plans, none are quite as excited about them as Missy. She gleefully celebrates the destruction she has caused and revels in getting The Doctor's attention.
Missy's Love Of Pretense
Almost every incarnation of The Master loves a good disguise as seen previously with Professor Yana and Harold Saxon which is what makes them one of the best Timelords from Doctor Who. That being said, Missy loves to pretend and deceive even without the help of a disguise.
When she first reunites with The Doctor, she pretends to be a droid seemingly for no other reason than her own enjoyment and to taunt her old nemesis. In a truly meta scene for the show and in one of Missy’s best moments, she delightfully pretends to be The Doctor (or Doctor Who as she calls him) in season 10 and renames his companions "Exposition" and "Comic Relief". Missy shares her love of pretense with her other incarnations but the way she delights in it is truly amusing.
Missy Reveals Her True Identity
In season 8, Missy has the upper hand over The Doctor as he has no idea who she is, something she takes great delight in. After dropping her pretense of being an assistance Droid, she drops many tongue-in-cheek and not-so-subtle hints about her true identity.
Despite his high intelligence, The Doctor remains oblivious to her true identity. After revealing she is working with The Cybermen, Missy also reveals the true origins of her name to The Doctor. In one of Missy's best scenes from the show, she is overjoyed by the Doctor's confusion and sees her ability to deceive him as a triumph.
Missy's Dark Humor
Although she is often scheming and murdering, Missy is also known for her outrageous one-liners. In season 8, she often uses the line, ‘say something nice’ and then waits for her victims to obey before killing them.
The scene where she taunts Osgood is particularly tense; she is handcuffed but is surprisingly unfazed about it which immediately signposts to the audience that Missy, as has been seen with The Master many times before, already has a way out. Missy beckons Osgood to come closer and then whispers to tell her she is about to kill her before adding that it's "their secret girl plan." Even in her darkest moments, Missy uses humor in order to distract and confuse her victims, much more so than her previous regenerations.
Missy's Singing At Inappropriate Moments
Despite being one of The Doctor's most threatening adversaries, The Master is no stranger to a bizarre musical number. When the character is in their Harold Saxon incarnation, they sing and dance while wheeling an aged Tenth Doctor around. Missy continues this trait, often breaking out into song, sometimes to unnerve her victims - as seen with Osgood - or simply to entertain herself like when she is locked in a cell with Clara and The Doctor.
While this shows just how disturbed she really is, it is a fun and unique aspect of the character. Her menacing and self-inserting take on the song ‘Hey Mickey’ also shows just how narcissistic she is.
Missy's Fearlessness With The Daleks
In the opening story of season 9, Missy, Clara, and The Doctor find themselves on Skaro with Davros and the Daleks. As the Daleks are one of the best Doctor Who monsters, it is surprising to see Missy's lack of fear here. Whether this is a manipulation tactic to confuse them or a genuine lack of care, it is strangely comical.
When the aliens rant in their usual Dalek fashion, Missy is unfazed and dances around to their angry screeching. Later, she meets the creator of the Daleks, Davros, bringing together two of the show's most iconic villains. Any other incarnation of The Master might seize this opportunity for a showdown but Missy, clearly offended by the suggestion that he is The Doctor's worst enemy, pokes Davros in his blue "eye" before gleefully running away.
Missy's Bizarre Relationship With Clara
Although Missy is partly responsible for her boyfriend Danny's death, Clara is forced to work with her in the opening story of season 9. Throughout the story, Clara is understandably uneasy around Missy. In one scene, Missy compares The Doctor's companion to a puppy, and in another, she pushes her down a hole to see how deep the drop is.
However, in other scenes, she does protect Clara from the Daleks which leaves the audience guessing what she will do next. Ultimately, Missy persuades Clara to get inside a Dalek's casing and later tells The Doctor this was the one that ‘killed’ Clara. She clearly hopes he will take his rage out on the Dalek and mistakenly kill Clara; in this one story, many different sides to Missy are explored.
Missy's Unpredictable Nature
The Master has certainly always been an unpredictable and erratic character, but before Missy their actions are mostly predictably villainous. While Missy starts out in much the same way as her predecessors, callously taunting and killing innocent people.
While she certainly maintains her villainy throughout her storylines, there are instances where she is also helpful. For example, she protects Clara from the Daleks at times and also helps The Doctor during his confrontation with them. This means that when she pledges to change in season 10, the audience is left to wonder whether she is being truthful. The question mark over Missy’s true agenda is what makes the character so compelling.
Missy's New-Found Loyalty To The Doctor
It has always been fairly clear that The Master hates The Doctor but also secretly cares for them. That being said, all previous incarnations of The Master are happy to work against The Doctor and betray them at any given moment.
When Missy tells The Doctor that she is prepared to change and be better, it feels more like a typical trick that the character would play. The audience's suspicions are seemingly confirmed when Missy sides with her previous incarnation. However, although The Doctor never finds out the truth, it is revealed to the audience that Missy really was on his side all along and was genuinely trying to change.
Missy Kills The Master
The Doctor has come face to face with their previous and even unknown incarnations several times over the years and this usually leads to mayhem and comical hijinks. However, the end of season 10 turns this idea on its head when two incarnations of The Master come face to face. In one of the best Master stories from Doctor Who, the character of Razor is revealed to be the Harold Saxon Master who bizarrely flirts with his future self: Missy.
Throughout this story, it does appear that Missy has joined her former self to fight against The Doctor. However, in one last twist, she kills her former incarnation. Poetically, just as Missy proves her loyalty, she is struck down by her previous incarnation which shows she is the most morally complex version of The Master.