Speaking as part of the Legend of the Traveling TARDIS panel on YouTube, former Doctor Who script editor Andrew Cartmel spoke against giving too many details about the origins of the main character in Doctor Who. The script editor of the three seventh Doctor series insists that the design of his “Cartmel Masterplan” was to keep most of the Doctor’s history a mystery.

“…you could try and deepen the character of the Doctor but, as far as I was concerned, that was completely forbidden because the whole deal with the Doctor is that the Doctor should remain a mystery, a complete enigma because that’s where the show’s title came from. That was the unique selling point of the show back in 1963. We don’t know who the Doctor is so you can’t develop or deepen the Doctor or give him more of a backstory, although some people have in the past, I’ve never really approved of that.”

Having not seen the Series 12 episode, Cartmel could only speak to the revelations in The Timeless Children based on his his fellow panelists’ descriptions; with the Doctor having an origin alien to Gallifrey and the Time Lord’s ability to regenerate developed from experiments on the Doctor as an adopted foundling child.

“As soon as we delve into the minutia and into the fine detail of what [current showrunner Chris] Chibnall’s done – Chibnall’s obviously done a reset on it, which is great – but as soon as you start to specify that reset, you’re back in the same old problem that you’re explaining too much. You just want to say what you thought you knew was going on, you didn’t. It’s much more than that, and kind of leave it there…”

Cartmel took the time to explain the rationale behind his “Cartmel Masterplan”:

“…when I joined the show, the Doctor had become almost like a guest character in his own show. He had become inconsequential. He’d become a victim rather than the sort of powerful figure at the center of the show. And also, over the previous decades, more and more had become known about him and he was supposed to be this complete enigma but gradually that mystery had been chipped away.” It started with… He’s a Time Lord. Then there’s other Time Lords. Then he’s not even the boss Time Lord. And he could be disciplined by the Time Lords and he could be exiled to Earth and all this stuff and there were always good, solid story reasons to do those things, by which I mean they would provide you with a couple of weeks more material for your stories, but they had long-term detrimental effects because the more you did that, the less interesting the Doctor became.”

Cartmel went on to explain how he incorporated these revelations into his plan.

“It’s like he shrank with every iteration of that he became less and less of a formidable figure. I say ‘he’ and ‘him’ because, up ‘til then he had been a male Doctor. So I realized that the thing I needed to do make the Doctor really powerful again and interesting was to give him back some mystery. And I always emphasized – people often ask – well you see I didn’t want to deny all the previous material that had come along, all that canonical material, I wanted to say ‘all that’s true but there’s something else that’s true.’ So the idea was that the Doctor was all those things but in fact he had a secret and that he was not just a Time Lord. He was some kind of potent pre-Time Lord figure who is passing as a Time Lord.”

This description integrates with the Timeless Child mythology Chris Chibnall introduced, but Cartmel’s plan never intended to elaborate on the Doctor’s secret.

“And people ask what exactly did I want him to be and the answer is well of course I didn’t have an exact answer for that because as soon as you have another exact answer, you’ve brought [the Doctor] down to Earth again and you’ve removed the mystery, removed the question mark in the title, So the idea was just to say, ‘this is what he isn’t. He is something greater and more mysterious and prior to that ’, but not to specify, because as soon as you specify it, the air goes out of the balloon again.”

“All I wanted to do was throw the Doctor back into shadow again and just give hints of what was going on and it sounds like there’s a lot of detail and specifics, which is the last thing you want. Number one, it depletes the mystery.”

Speaking with a love of the series, Cartmel aptly described what he finds most exciting about the Doctor:

“When you hear that [the Doctor’s opponents] are slightly afraid of him, you get this little tingle in your spine. And that’s whole thing we’re aspiring to, is that slightly spine-tingling, slightly hair-raising sense of wonder about the Doctor. Who Is this guy or this gal? And you want that bit of gooseflesh. And as soon as that gooseflesh is gone, your goose is cooked!”

So, has Chris Chibnall taken all the mystery out of the Doctor? Many mysteries remain. We still have the mystery of the Doctor’s origin as the foundling known as the Timeless Child. We still don’t know what type of being the Doctor is, where she came from and why she was found alone and seemingly abandoned. We don’t know the machinations of The Division and what the Doctor did while she worked for the secret Time Lord agency. We also don’t know where the Fugitive Doctor’s incarnation fits in the regeneration timeline.

If Chris Chibnall takes a true cue from the Cartmel Masterplan, as Andrew Cartmel describes it, we may never find out all the answers to the mysteries introduced in Doctor Who Series 12.