Cast your mind back to 2010. The Master seemingly saved the Doctor and got revenge on Rassilon for that never-ending drumbeat. Off he went, back to Gallifrey – probably.
Surely one of the most fun things to speculate on is what happened to the Master between the conclusion of The End of Time and his reappearance with a (dramatically) changed appearance as Missy, serving tea to dead folk, in Series 8.
Join us as we explore just what he/she was up to in the intervening years!

1. Back into Hell

The last we saw of the Master in The End of Time was him sacrificing himself to foil Rassilon’s plan to escape the time lock and restore Gallifrey. Presumably he ended up back on his home world, at that moment being ravaged by the Time War. It’s fair to say that big chief Rassilon and the other top Time Lords wouldn’t have been best pleased, but in the midst of all that chaos would there have been an opportunity to escape?
The Master had certainly got out of some pretty tight spots before – maybe he quickly donned a rubber mask and slipped away, cackling as he did so? Or perhaps he came out the winner of his struggle with Rassilon, forcing the old boy to regenerate into Donald Sumpter. I like to think the Master briefly assumed the presidency…

2. Cooking Up Dastardly Plans

Perhaps the Master didn’t stick around when he got back to Gallifrey. Recognising he most definitely was not among friends there, maybe he stole a TARDIS and made a swift exit. Hell, there’s a whole universe out there to explore – no need to stick around in one place. Gallifrey was, of course, time locked and inaccessible (a bit like Scunthorpe) until the Doctors came together to restore it in The Day of the Doctor but, being an ingenious sort, could the Master have found a means to get away, thus freeing himself to get up to all kinds of mischief on other worlds?
And the Doctor wouldn’t have been there to stop him!

3. Had The Drums Removed

Okay, that sounds flippant but there’s a serious point here. The John Simm version of the Master was plagued by the drumming in his head, and in The End of Time this is revealed to have been planted there by Rassilon as a signal to ultimately enable Gallifrey to escape the Time War (do keep up). This cast the character in a rather more sympathetic light than before, as a desperate man driven to do terrible things because of the Time Lords’ malign influence – mad rather than bad.
By the time we meet Missy this doesn’t seem to be a problem any more, though she could hardly be described as well-balanced. Perhaps the Master had some kind of treatment to get rid of the noise that plagued him? Do they have counselling on Gallifrey?

4. Lived The Quiet Life

You know what, maybe the Master decided to take things easy after the events of The End of Time. He couldn’t be blamed if he did – things most certainly had not gone well for him and to cap it all, he discovered he’d basically been used as a means for Timothy Dalton to get what he wanted. The Master has form when it comes to disappearing for extended periods and in Utopia we see him living a very different sort of life as a kindly old professor at the edge of the universe.
Maybe he just laid low for a while, content to wait for his opportunity and recharge his batteries? No, I can’t see it either…

5. Became a Monk

Sick of the drumming, shouting, disguises, and failed attempts at universal domination, the Master opted for a quiet life, joining a monastery for contemplation and reflection upon the dastardly deeds of his previous lives. There’s no way our other favourite Time Lord can be all bad, not with all of those times he and the Doctor have found themselves teaming up.
Of course, had he spent time in a monastery, there is no doubt that the Master would only have got bored eventually, unseating the abbot and taking over.

6. Performed a West End Musical

He’s a natural.

And The Thing (S)he Definitely Did Do

In the midst of all this speculation the one thing we most definitely can say is that at some point the Master changed gender (and then thought it might be nice to celebrate the Doctor’s birthday by giving him an army of Cybermen. As you do). The series had established in recent years that Time Lords can change sex when they regenerate – and have even seen it happen with the General in Hell Bent – but is this what happened? Did the Master become Missy not by regeneration but another heinous act of body theft, a la Tremas and Eric Roberts?

There’s surely a great bit of fan-fiction to be written to fill in this gap, which sees the Master using his considerable charm and dancing skills to woo a good-hearted Scottish lady who is so delighted to have finally met the right one. Only it all ends horribly, in a dreadful moment of realisation that this is a man really only interested in one thing…

But enough of what we think! You’ve read our (not entirely serious) theories but what do you reckon the Master was up to before he was Missy? Let us know!

(Adapted from an article originally published on Kasterborous in February 2015.)