“The thing about Doctor Who is, it’s a tremendously flexible show,” departing showrunner Steven Moffat said of the long-running Time Lord series soon launching its 13th Doctor and first woman in the role of the dual-hearted Gallifreyan. “It’s tremendously light on its feet, and being tremendously light on its feet means it also changes episode to episode as opposed to just era to era,” the Emmy-winning Sherlock EP added on ahead of Doctor Who’s Comic-Con panel.

Today’s Hall H congregation not only closes out this year’s Comic-Con but also will be the last appearance for Moffat and the 12th Doctor Peter Capaldi leading the beloved BBC America series. Both Comic-Con vets, they will be joined onstage for what is sure to be an emotionally charged event by Pearl Mackie (current companion Bill Potts), Matt Lucas (Nardole), Michelle Gomez (Missy) and Mark Gatiss, who also writes and stars on Sherlock. The Doctor Who farewell will see fans treated to a glimpse of the just-wrapped Christmas special in which Capaldi’s Doctor regenerates into the new Doctor, played by Broadchurch alum Jodie Whittaker.

Having spent a few days already at the San Diego confab, Moffat chatted with me about the end of his tenure, the pleasure of working with Capaldi personally and professionally over the past three seasons of the show, and Whittaker and new showrunner Chris Chibnall taking over. As he did earlier at SDCC 2017, Moffat also ventured a little bit into a possible next season of the Benedict Cumberbatch- and Martin Freeman-starring Sherlock and what is happening with the Dracula miniseries he and Gatiss are conjuring with producer Sue Vertue for the BBC.

DEADLINE: You are showing some of the Christmas special here at Comic-Con. How far along is it?

MOFFAT: It is done. We’ve wrapped the thing a few days ago. I say wrapped. We have a couple of extra things to do. We didn’t do the new Doctor part yet, because that’s the other team do that. The new team comes in and does their new Doctor bit, but the main part of it is done.

DEADLINE: And what will we see in that main part?

MOFFAT: As you already know if you saw the end of the last episode, it contains two Doctors. The 12th Doctor meets his earliest incarnation, the first Doctor, as now played by David Bradley. I don’t want to say too much actually, but it’s the two of them. Both of them different. One man facing one problem at two different points in his life, and doing it face-to-face with himself.

Peter Capaldi’s Doctor trying to explain to the first Doctor why he must go on is inevitably convincing himself at the same time, but you know, there’s an adventure. There’s a threat. There’s all that stuff going on, but it’s far too far out for us to say more than that. You’ll get a glimpse of what we’re up to in the trailer that we’ll show.

DEADLINE: How does the process work of you handing over the reins in the special to Chris Chibnall?

MOFFAT: It literally is as it was the last time, though the line is slightly more thickly drawn this time I suppose. We make sure right up into the point where Peter Capaldi explodes in a ball of flame as he starts to regenerate, and they come in and the last set, the best very small set, is written by Chris Chibnall and features the new Doctor recovering from the regeneration. That’s exactly what we did the last time with David Tennant in “The End Of Time.”

At that point, the remaining page was written by me, and we shot it all in the same day on that occasion because the scheduling was slightly different. Russell Davis handed me headphones and wandered off, and I sat there and watched the monitor instead of Russell. So like that, it wasn’t quite as dramatic as it sounds because in fact, David Tennant still had I think two or three more days to shoot as the Doctor on that show after the regeneration was filmed. In this case, Peter Capaldi’s very last moment is his moment where he starts to regenerate, and there was a gap between filming one bit and filming the next.

DEADLINE: So, what do you think of Jodie Whittaker as the new Doctor, the first female Doctor?

MOFFAT: What an amazing, inspiring choice! Jodie Whittaker is never less than brilliant in everything she does, and now the whole universe is her stage. And best of all, little girls everywhere know the stars can be theirs.

DEADLINE: You took over the show in 2010 with Matt Smith becoming the Doctor and then also ran it with Peter as the 12th Doctor. For you, what defined those tenures?

MOFFAT: The thing about Doctor Who is it’s a tremendously flexible show. It’s tremendously light on its feet, and being tremendously light on its feet means it also changes episode to episode as opposed to just era to era, you know.

Now with the Matt Smith era, we fashioned the show around the entirely brilliant Matt Smith, and then we fashioned the show around the entirely brilliant Peter Capaldi, but rather than thinking, oh, we’re going to turn this show into this kind of series, we don’t. We tend to think, what is this show this week? Is it a comedy this week? Is it a love story this week? Is it a horror story? You don’t want to impose a huge agenda on a show whose primary virtue is its utter fluidity and flexibility. You want to say Doctor Who will be whatever damn show it wants to be every time the Doctor walks out The TARDIS.

DEADLINE: Which is also a lot of responsibility, considering the show’s legacy and international popularity…

MOFFAT: I mean, it’s like curating a national treasure when you take over Doctor Who. You want to look after it. You want to make sure it’s always at the top of every list. So that, just that really, the fact it’s still here and going on to a new Doctor and a new showrunner, that’s the big deal for me.

DEADLINE: So, what’s been the highlight for you?

MOFFAT: I think given that we just walked out of the studio for the last time a few days ago it may be a little early for me to try and work that out. I’d always wanted to work with Peter. He was an actor I wanted to work with for years. When I realized during my time on the show that he was a Doctor Who fan I thought well, you know, this would be a terrible missed opportunity if nobody ever thought of handing the TARDIS to him.

DEADLINE: What was that like, from the perspective of just finishing filming his exit from the TARDIS?

MOFFAT: He has an extraordinary sensibility, and a passion, and a fearlessness about how he plays that part, and a willingness which I think is very interesting. You can see it in Tom Baker, you can see it in William Hartnell, you can see it in Peter Capaldi. Basically saying, “I’m trying to save everybody’s life. I’m not trying to be popular.” You know, that’s not the point. I’m kind but I’m not always nice, and I like that. I like that his willingness not…I know he can be very charming, but sometimes he’s quite willing to go the other way and say, “I’ll do what’s got to be done.” I mean, he had to save people. I’m not running a cocktail party. I like that. I think that’s been tremendous.

Getting to know Peter as a friend, we’re very good friends now, has been a lovely experience for me. He’s such a kind and literate and clever man, so talented. That’s just been joyous. He’s very funny too, so yeah. He’s great. He’s a great man.

DEADLINE: This is a show that started in 1963, has gone through over a dozen actors as its leads, dozens of companions, 16 years off the air to be revived in 2005 and now bigger than ever. Why do you think it has endured and thrived?

MOFFAT: I like to say that one of the reasons Doctor Who is very popular is it’s very good. Even if you can’t stand science fiction and you want something more serious, there’s that here too, but if you like this kind of show, you’re going to like Doctor Who. It’s incredibly well done. It’s made with real passion and commitment and I hate to sound like I’m boasting, but have you seen the list of people who write Doctor Who?

You know, the number of showrunners who have their own shows who turn up to do individual episodes of Doctor Who is astonishing. No other show’s got a writing team like it. This isn’t an everyday event. I stop to think when whatever distant day Doctor Who goes off for a while, people might look back on this and think, how the hell did that happen to an hourly evening family adventure series? How did that come about? How did all that happen? I do think it’s an extremely good show.

DEADLINE: One barrier has been broken now with a female Doctor cast, you had a female Master in Missy, and this year you had a lesbian companion in the Pearl Mackie-portrayed Bill Potts. Where you surprised by some of the initial response to the announcement of the character?

MOFFAT: I was only surprised in good ways. I was nervous when it first got out, and there was much more fuss for a couple of days than I thought there would be. I thought, for heaven’s sake, surely we’re past thinking that’s a big deal, and then I was surprised in good ways because everyone just settled down and I loved the character. She was a huge hit, and her sexuality was actually barely mentioned, and that’s kind of the way it should be.

DEADLINE: Speaking of fusses of a very different type, you spoke about it a bit earlier during Comic-Con, but with Doctor Who over for you, will a new installment of Sherlock be in the works?

MOFFAT: At this point we honestly don’t know. I sort of vaguely assumed that we do it again at some point. I haven’t had time to think about Sherlock, and Mark’s been hugely hard at work of course a range of projects including Doctor Who. So we haven’t had time to sit down and work out what we do with a series five.

DEADLINE: Sounds like it is more than a vague thought…

MOFFAT: We all love doing it very much. No one’s against it. No one’s doing it because they have to, you know. Everyone can survive perfectly well without it, and that’s been the case for a long while. So the only reason we do the show is because we love doing it. That, of course, has the downside that if we ever think we’re just turning up and doing it for the sake of it, we don’t want to do that, but you know, I mean, I sort of vaguely assume that at some point in the future, whenever that is, we’ll do some more Sherlock Holmes.

DEADLINE: Of course, you and Mark now also working on a Dracula miniseries with Sue for the BBC. Where is that at and would it come before or after a new Sherlock?

MOFFAT: It’s far too early for us to say anything outside of the tiny little circle of me and Mark and Sue about how we’re going to handle it, but I think we’ve got good ideas. We’ve discussed what we think are the key things that should be done with Dracula, but I don’t think we’ll be sitting down for a few months yet to actually start hammering that out. We’re just putting a flag on it and saying we’re going to do it really, but I think we’re on to something.

DEADLINE: You’re a Comic-Con vet, you’ve been here most of this year’s convention, on panels, watching panels. With the end of your and Peter’s time on Doctor Who and the big Hall H goodbye on Sunday, what does Comic-Con mean to you?

MOFFAT: Oh, I like the Comic-Con itself, by which I don’t mean the bit that I do. I mean wandering around the convention floor with my son and looking at things, and getting to see things. Getting to meet people I’d never expect to meet, and looking at the amazing costumes, and just that whole city full of people who are so utterly happy. I absolutely love it.

At some point every time I’m here I’ll have to go and do the guest panels and interviews and all that, but really I like the Comic-Con itself.