Spoiler Alert

The newest era of Doctor Who is welcoming new fans with open arms as they hop into the TARDIS with the Fifteenth Doctor and Ruby Sunday. The long-running series somehow feels fresh once again, infusing season one’s first few stories with humor, heart, and cheeky musical numbers. But Doctor Who’s latest episode, “Boom,” turns the series on its head with an extremely tense story that tackles death, faith, and the dangers of traveling across space and time. What happens when the Doctor is stuck on a landmine and has to spend the entire episode in one place? “Boom” marks the triumphant return of former Doctor Who showrunner and writer Steven Moffat, who returns to the series after seven years. We sat down with this Whoniverse creative legend to talk about the episode’s themes, why he returned now, and raising the stakes for the Doctor. 

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Nerdist: Where did the inspiration or idea for “Boom” come from? 

Steven Moffat: Episode one of “Genesis of the Daleks” in which the Doctor steps on a landmine and is stuck there for two minutes. I always loved that little bit, even when I was a kid. And I just thought I wanted the idea of a tension-based episode that sort of strands the Doctor and makes him unable to do all his normal stuff. So we have the Doctor on a knife-edge throughout. Doctor Who rarely does tension, it mostly does action adventure or romance or comedy or musicals these days, but the one thing it doesn’t touch on much is suspense… the Doctor on a landmine for an entire episode was all my childhood dreams come true.

This episode absolutely gives us prolonged tension in a way that we don’t often get in the show. As you were writing and formulating the script, what were some changes that you had to make to really keep that tension and those elevated emotions throughout it?

Moffat: Do you know what? There was one big change. I got about 15 pages in when I was writing it, and then I threw those 15 pages away because it wasn’t working! I needed to get him on the landmine quicker and the tension needed to kick in sooner, and I was just faffing about having them chat. So that was a big gear change for me… I [knew I’d have] to set it up and make sure that I didn’t just put him on a landmine, but moment by moment, he’s got to have the worst day you could have on a landmine… if his day just gets worse and worse, that monitors your mood state, that was what I was looking for.

Indeed. You know, we’re pretty early in the 15th Doctor’s era, and “Boom” gave us, for the first time, a different side of him. We got to see him in a much more serious and really vulnerable light. I’m really curious about what kind of conversations you had with Ncuti and/or Russell about conveying the emotional weight of this episode.

Moffat: It was quite early on in Ncuti’s filming of the Doctor, so it was quite early for him… I remember at the very beginning, I had a long chat with Russell about how far do we push him? I mean, how far into despair, how raw must the emotion be? And he was keen that the Doctor stay, because he’s a new doctor, magnificently in control. And I was keen that no, we push him a bit past that. We get him a bit more helpless. So I think we got between the two of us, to the right place, the Doctor facing absolute defeat and then saved by a means that he initiates but doesn’t understand what he’s done.

So it’s a tough judgment and it’s always difficult if it’s a new Doctor. I mean, if this was the third season with Ncuti, you’d know what [his Doctor] was like. You’d know all these things and you could do something slightly different with it, and you always do. But this audience is still getting to know him. And what they get to know here is, that actually, if push comes to shove, you can still see that Peter Capaldi’s Doctor is still in there. William Hartnell’s still in there. Tom Baker’s still in there, the glowering monolith that he becomes. He’s been dancing and fun and it’s all been great, and then suddenly, he’s the towering monolith who can scare people with these eyes. You need to see that side of him. Heroes have to be dangerous. They’re just dangerous in a nice direction.

BBC/Bad Wolf Studios/Disney+

Absolutely. There were so many great themes that played into this episode. Two things that really resonated with me was faith and how it was approached as well as reframing how we view death. Why did you want to lean into those themes specifically, and what was it like trying to intersperse them in with the usual beats of a Doctor Who episode?

Moffat: It’s not me making some great meditation on faith. I don’t have one, but the Doctor is interesting when it comes to faith. ‘Cause he’s always, as he was in “The Time of Angels” with Father Octavian, quite disparaging of it, except he’s got faith in so many things. He has faith that there’s order to the universe, that truth and beauty are the same thing, that it will all make sense in the end. He has faith in those things. So when he disparages faith, he’s a complete hypocrite. 

Equally, when he disparages soldiers for their profession, he conveniently forgets he’s the finest warrior in the universe. As I keep saying, all loathing is self-loathing. So he’s interesting in that subject. He comes to love Mundy, of course, and he actually respects her faith. I’m worried when people ask [why faith is a part of the episode], that they think I’m disparaging it. I’m not disparaging at all.

I don’t think the Doctor is right about everything, I don’t think he is. I think he’s crazy. And he’s got a slight fantasy about himself. He always says, “I just wander and explore,” and you want to say, “No, you look at the nearest fight, run into the middle of it and decide who should win. That’s who you are. You’re not just looking at the fairy lights.” So I think it’s interesting to place him in that world. It also allows Ruby to see he’s nuts and he’s a terrifying man. And you need to know that about the Doctor if you’re going to be his best friend.

That’s such an important part of when you have a new companion come on, right? They need to see all those sides of the Doctor because you’re drawn in as a human by the wonder and the magic of it all, and you get to travel and go to all these exotic places. But there are real stakes that come with that, and there’s a real possibility of people getting hurt or worse. And so this episode was kind of really her wake-up call to, “This is dangerous business I’m into.”

Moffat: That’s right. That’s exactly what it is. We did a good scene in “Thin Ice” with Bill Potts when she asked [the Doctor], “Have you ever killed anyone?” And he has to answer that question. You need moments like that. You realize, “Whoa, this guy is something else. He’s not just cuddly.” He is cuddly and he is lovely, but my God, he’s dangerous.

BBC/Bad Wolf Studios/Disney+

Right, yeah. You know, another thing I liked about this episode was how it approaches the “evil.” Sometimes in Doctor Who, you have these very scary baddies, like the Weeping Angels and the Daleks, but you don’t have that here. How do you think shifting away from that classic “villain” changes the dynamic of everything that’s happening?

Moffat: It’s a good demonstration of how he really works. I mean, you’ve got the Doctor Who stories, of which I’ve written many, where there’s an implacable evil like the Daleks, Weeping Angels, and many others. And then you’ve got other stories like “The Empty Child,” where he figures out, no, it’s not what he thinks it is… I like stories like this because the Doctor can solve the mystery and he can actually say, “If you just look at it from another angle, it’s not so scary. It’s this.” And it is a horrible one that he reveals in “Boom,” which you must not reveal in advance. There is no one here, it’s your own hardware. I like that kind of story. I think it’s a useful kind.

It definitely challenges the Doctor in a specific way. I think so many fans are excited for your return to Doctor Who. Why did you decide to do it after so many years? 

Moffat: I don’t know. It makes no sense at all. I’ve done it again! It was [returning showrunner] Russell [T Davies] going back, and I was sort of bemused. I ended up unwisely talking to him and saying, “Why are you doing that? Why are you going back? You always said you’d never go back.” And so we ended up just chatting away on the phone and by email, and I was just asking him, “What are your plans?” And he was saying, “Would you ever write one?” And I was saying, “No, I think I’ve done everything.” 

I didn’t mean everything that I’m capable of. I thought, “Well, actually, suspenseful tension, I haven’t done that.” And suddenly I think, “Actually, I could write that.” And Russell was so instantly, so wildly enthusiastic about the idea. I mean, instantly. I sent him the email and I think he responded like 30 seconds later. He said, “Yeah, write that.” So I thought, “Well, what does it matter? I’ll do one more.”

We are so glad you did. “Boom” is going to thrill the fandom for sure because it is an excellent episode. 

Moffat: I’m happy to hear that! I’m pleased. I really am so pleased.