Dark Water revealed that Missy, the mysterious Mary Poppins-like character played by Michelle Gomez, is actually long-time villain The Master in a new body. Despite originally claiming to be an android (“Mobile Intelligence Systems Interface”) Missy eventually dropped the charade, gloating to the Doctor: “Try to keep up. I’m Missy. Short for Mistress. Well, couldn’t very well keep calling myself the Master, could I?”
So if you were one of the many people who put forward exactly that theory, give yourself a pat on the back. The speculation had been building ever since Missy first started appearing to dead people in Deep Breath, the first episode in series eight. Some of the fan theories were… outlandish to say the least. Security around the plot was tight, with key scenes being removed from previews given to journalists and critics.
Missy marks the first time we have seen a Time Lord (“Time Lady, please. I’m old fashioned”) change genders during a regeneration, although the idea has been alluded to before. The Master, as played by John Simm, was last seen heading back into the Time War in 2010’s The End of Time, David Tennant’s final episode. She seems to hold a grudge, telling the Doctor she was “the one you abandoned. The one you left for dead. Didn’t you ever think I would find my way back?”
The clues were all there. The fixation with the Doctor. The mania. The odd dress sense. Plus it makes sense that The Master would have the phone number to the Tardis. After all, he did steal it once. All it took for the Doctor to realise Missy’s new identity was a sloppy kiss and a lingering feel of her twin Time Lord hearts.
The Mistress is playing the long game this time, from apparently bringing the Doctor and Clara together in the first place (earlier in the series she claimed she ‘chose’ Clara) to working with the Cybermen. But to what end? World domination and shaky alliances have been the Master’s raison d’être since Roger Delgado first played him in Terror of the Autons, but an army of the dead is a particularly twisted method.
As in all the best mysteries (at least in Doctor Who) the answer only raises more questions. How did the Mistress escape the Time War? When did she regenerate? Is St Paul’s Cathedral her Tardis in disguise? Does she actually fancy her life long adversary, or is all the flirting simply to mess with the Doctor’s mind? We’ll have to wait until next week to find out.