Doctor Who exclusive: Steven Moffat reveals the secrets of Extremis

Brave the Veritas! The showrunner talks us through episode six, discussing Missy’s return, the Doctor's blindness, River’s diary, the Pope and the US president… SPOILERS!

Patrick Mulkern: You have certain key elements running over several episodes. How did the idea of the Doctor’s blindness arise? Was it solely something in Jamie Mathieson’s Oxygen script that you decided to run with?


Steven Moffat: I was looking for something in the middle of the run – a big twist, a shock. For a while we sat around wondering if we could blow up the whole planet Earth, but that seemed a bit drastic, and we’d have to reverse it pretty quickly anyway. It’s the kind of idea that’s too big for anyone to relate to, and you know it can’t hold.

But the Doctor blinded? When I read that in Jamie’s script, I was horrified and gripped and amazed – as I hope you all were when you watched it. Such a brutal demonstration that, yes, space is dangerous. Then, of course, he gets cured a few pages later, and somehow that weakened it. So I bit the bullet. He stays blind. For once, the Doctor takes a hit! What the hell does he do now?

Mulkern: The Haereticum/Veritas storyline (with its Catholic priests, creepy Monks and a library with a deadly text) reminds me of The Name of the Rose. Was that at the back of your mind or were there other influences?

Moffat: Name of the Rose, I loved. The Da Vinci Code was great fun. And it’s just a world Doctor Who hasn’t played much in. But there are catacombs and frocks and sinister choirs, so it’s all very him.


Mulkern: The Pope walking in on Bill’s date with Penny is one of the funniest moments in Doctor Who. It’s equally bizarre seeing him and his cardinals inside the Tardis. What qualms did you have about bringing the Catholic Church and the Pope into the Doctor Who world?

Moffat: Well, I’m not religious myself, in any way, but I’m mindful that many people in our audience are, so I tried to walk the line with care. The Doctor is always irreverent in the face of an authority figure, and the Pope could not be exempt – but on the other hand he takes his holiness seriously when he realises there’s danger in the Vatican.

Like the Doctor, we treat the whole matter with respect, but not with reverence. Offending or hurting people is never clever – but being funny is always fine. Well, I hope so, anyway.

Mulkern: At certain moments His Holiness is exempt from the Time Lord gift of translation and heard speaking only in Italian. Why is that?

Moffat: Well, the scenes just worked better with the Pope speaking Italian and being translated. I did write in the Doctor saying he didn’t really need the translation, and Nardole suggesting that he play along out of courtesy – but it glitched the scene, so I lost it in the edit. In fairness, the Doctor’s translation ability has wobbled before, so it’s just having another off moment. I tell myself it’s because of the blindness, and the concentration involved in interpreting the world through his sonic sunglasses. (Hooray, they’re back – a nation cheers!)

Mulkern: You also have a bit of fun with a bygone Pope – Benedict IX, who had a scandalous reputation in the 1100s. You’ve turned him into a sort of Wicked Lady and past amour of the Doctor…

Moffat: Yep, and it’s all true. The night, and the music, and those castanets…

Mulkern: When was Extremis filmed – before the US presidential election? How did you resist the temptation to depict the president who’s just committed suicide as either Donald Trump or Hillary Clinton?

Moffat: It was written before the election, and shot after. I noted in the script that the gender of the president was yet undetermined, but we’d know by the time we were in the studio. It’s not every day you get to choose which president to kill…


Mulkern: The “simulant” Doctor says the Monks have created “a holographic simulation of all of Earth’s history”. But I suppose they haven’t been running it for all of Earth’s history – and this “game” is something they’ve set up relatively recently…

Moffat: It was set up fairly recently, but the software simulates all of human history from the beginning. It runs much faster than real time, of course.

Mulkern: Confession time. One point in Extremis still puzzles me. Nardole says he’s followed the Doctor from Darillium on the express orders of his late wife River Song – but how has Nardole come by her diary? After River died in the 2008 two-parter Silence in the Library/Forest of the Dead, David Tennant’s Doctor left her diary behind in the Library.

Moffat: Short answer: you can always get a book out of a library.

Slightly longer answer: the Tenth Doctor had no choice but leave it there – it was full of incendiary information about his future. But once that future was lived, he’d have to get it back some time. He couldn’t leave all that confidential stuff lying around in a Vashta Nerada-infested library, could he? So one day Nardole got it for him. (Actually, there’s a whole story in my head about this, but not one I’ll ever get to write now. The last time he sees River – it’s terribly sad.)

Mulkern: I don’t wish to sound rude but what is it with you and libraries that connect with virtual-reality environments?

Moffat: Books ARE virtual reality.

Mulkern: One final question: why did you call it Extremis?

Moffat: For me the whole point of the story is the Doctor is still the Doctor, even in extremis. Even when he’s not real, even when he’s a simulant on a hard drive and there is no possibility of escape or reward, he holds true to the man he wants to be. Never cruel, never cowardly – and never giving up till he wins.

RT’s review of Extremis ★★★★★


In April, Steven Moffat was inducted into the Radio Times Hall of Fame