Steven Moffat talks Doctor Who return, writing for Ncuti Gatwa and future reunions

“Nobody ever really seems to leave the show completely. The cast all have a sort of afterlife of Doctor Who, because they go and do conventions and all that stuff. And now I’m actually back writing some silly episode.”

Unlike his Doctors, however, not many would have expected Steven Moffat to be back working on Doctor Who in 2024 – despite him being very good at the job. Nearly two decades ago, the now 62-year-old was the guest-writing “ringer” behind the most popular episodes under then-series boss Russell T Davies.

Then, in 2010 he was the natural choice to take over when Davies departed, powering through seven years, six series, two Doctors (Capaldi and Smith) and a 50th-anniversary special that beat the odds to become a critical and ratings hit.

When he left in 2017, he’d written more Doctor Who than anyone living and seemed content to leave it there, moving on to write big new dramas for Netflix and HBO. But this week, Moffat is back at the Tardis controls for an episode starring Ncuti Gatwa’s new Doctor. Apparently, returning showrunner Russell T Davies made Moffat an offer he couldn’t refuse, recounting in several interviews how he got Moffat back on board with his first or second phone call after being given the job.

Moffat remembers things a little differently – apparently the conversation actually started over email, and it took a little longer to persuade him to return. But he agrees what finally hooked him was the promise of something new. “You’ve got to remember, I’d written 42 solo scripts – not counting co-writing or the ones I rewrote,” he says. “I thought I’d done everything – twice. And if there isn’t anything new for me to do, I can’t see the point in doing it.

“But then I thought, ‘Well, I haven’t done tension. I haven’t done suspense – edge-of-your-seat suspense.’ Whether or not I succeeded in doing that, of course, is a different matter. But that’s what I was aiming for.”

So what was this (literally) killer idea? Well, Moffat suggests he was inspired by a moment from the classic 1975 adventure Genesis of the Daleks, where Tom Baker’s Doctor briefly steps on a landmine. What if, he thought, that became an entire episode? He adds, “It was pretty much a one-line pitch: ‘He’s standing on a landmine, and he can’t move, and he has to do everything the Doctor does while standing on a landmine.’”

Hence, presumably, the episode title – Boom.

“Doctor Who doesn’t often do that tension,” Moffat continues. “You might think it does. It does scary, it does funny, action, even musicals. But not tension or suspense. And that’s in part because no character switches off suspense like the Doctor, because he comes in, makes a joke and defeats the enemy, every single time.

“So to make him the focus of the jeopardy, and to have him on a knife edge where one wrong move and he literally blows everything up – I just thought that was a new thing for me to do.”

He adds, “It’s quite an about-face. If you’ve seen the first two episodes [of this series], this will arrive like a bloody shock, I’ll tell you. It’s quite different! But that’s the nature of the beast.”

With Moffat’s experience, pedigree and a strong concept in place you might assume the new script poured out of him like water – but script number 43, he says, was just as hard as any of the ones that came before.

“It was a surprise to me that experience didn’t grant me more benefits,” he says ruefully. “I got 12 or 15 pages in, and realised I’d got it all wrong. I’d written some stuff that I really liked. Some good jokes. And I thought, ‘No, it’s all wrong. It’s all wrong.’ So I threw it all away, and started again.

“The plot didn’t kick in fast enough. I was faffing about, having the Doctor and Ruby having a fun chat and introducing an alien planet.

“And that can work fine. I mean, the first half of Silence in the Library all those years ago, it’s just them wandering around a library. And I kept thinking, ‘Do I need to speed that up?’ And I thought,’ No, it’s quite nice. I like it. Let’s just have them go for a stroll and a chat.’ That worked. But it wasn’t right for this one.

“There’s a lot of real time in this, moment to moment. It really is one tightly focused dilemma, which is a challenge. But, you know, there’s always something in Doctor Who that’s difficult.”

Not that it was entirely a slog. Despite being given a new Doctor to write – who when he started had yet to appear on screen – Moffat says that writing for Ncuti Gatwa’s new Time Lord was one of the easier parts of the gig, aided by Davies sharing his plans for the series and a viewing of the 32-year-old actor’s audition footage.

“I’ve only met Ncuti a few times – when I was on set, and at the read-throughs, and so on. So I can’t say I know him well,” he says. “But there’s a point at which, in any given Doctor Who story, the crisis hits and the Doctor just becomes the Doctor. All the flourishes that are different, or the eccentricities, or what I always think of as the Doctor’s pose, goes away – and the fast-talking, terrifying General surfaces.

“And you realise that that’s the real guy. He likes to play. He likes to play at being whatever he is this week, or in this incarnation – that’s great fun. But when a crisis hits, the Doctor is just the Doctor. It’s the same ancient, terrifying beast that’s looking out of those eyes. And that’s quite similar, really.”

Reverting back to hired gun after running the show for seven years was also less difficult than you might expect for Moffat – he points out that even when showrunning, he saw writing episodes as a separate job that he carved out specific time for. Though sometimes, he admits he reflexively returned to his old habits.

“It’s not as odd as it should be, partly I suppose because I was just reverting to the earliest job I had on the show, which was being an occasional episode writer,” he says.

“At the same time, it’s slightly disconcerting, because I remember at one point I was doing a tone meeting and I said, ‘What else have we got in the show we could pull money from? Oh, s**t, I’ve forgotten, I’m not in charge of budget! I don’t know what the rest of the series is.’

“My technique of saying ‘I’ll write that cheaper later’ didn’t play. But it’s certainly not an issue for me. I don’t have some mad, controlling impulse that I need to be in charge of everything.”

Though Moffat did indulge a little, he says, in reminding viewers of his tenure in subtle ways during the episode. Viewers may have to watch (and listen) carefully for the references, but they are there.

“It’s mostly new stuff,” he insists. “But, I mean, there are elements, and probably slightly too many, back-calls to stuff that I did.

“They’re just fleeting references. There’s not a lot. It’s very much new stuff. But there is stuff in there that you’ll recognise from old episodes. But my instinct was always to bring back something that everyone’s forgotten. I think it’s more fun.”

And any other teases, or surprises, from the episode more generally?

“Oh, there’s loads more for you to find out,” he laughs. “There’ll be a couple of surprises there, I guarantee you that. But I’m not telling you what they are.”

Clearly, to say any more about what awaits the Doctor would be a spoiler – and even on the sidelines, Moffat still delights in secrets. Just try asking him if he’ll be back for more episodes (beyond his recently-confirmed return for this year’s Christmas special).

“Let’s leave that to the future,” he says enigmatically. “I could well be done. It depends on if anyone wants me to, and if I’ve got an idea. Those are very big ifs. If they want new, young people, I wouldn’t blame them.”

But of course, his fellow former showrunner Davies came back with his former stars for the 60th anniversary... so could Moffat do something similar, returning for the 70th with Matt Smith and Karen Gillan, or Peter Capaldi and Jenna Coleman? Surprisingly, he doesn’t rule anything out.

“Well, I mean, I wouldn’t be against it,” he muses. “The Doctor and the Ponds ride again? I mean, yeah, why not?

“But I don’t know how many times you can do that. Again, that’s a decision for Russell, not me. Do you undercut your current Doctor by doing that? I always worry about that. I always worry about how many Doctors you should have at once. It’s Ncuti’s show now, and it should all be about him, really.

“But, you know, I loved those days, and I loved working with those people, and doing one-offs is fine – as long as it doesn’t take over my life again!”

He adds: “Whenever I finish something for Doctor Who now, I always sit and think, ‘Was that it? Is that it done? Am I finished? I’d better make the last line a good one because that could be the last one I ever write.’

“But I feel as though I’ve been making my exit for about 100 years now. So I’d better not make too much of a fuss. I’ll end up writing my last one and not realising it.”

And if this is Moffat’s final say on Who, at least he’ll be going out with a bang – or should that be a Boom?

A condensed version of this interview appeared in the 18th-24th May edition of Radio Times magazine, on sale now.

Doctor Who continues with Steven Moffat's Boom on 18th May on BBC iPlayer and BBC One.

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