Doctor Who finally returns to our screens on New Year’s Day with the first installment of Spyfall, a two-part adventure that is set to push the boundaries of the sci-fi franchise to its very limits.

Showrunner Chris Chibnall, now settled in for his second year in charge of the 56-year-old BBC series, says the series opener – the first of ten new episodes – is the show’s most ambitious yet.

“Episode one, I would say, is our most lavish, location-filled, action-packed episode, I think we've ever done,” Chibnall tells Yahoo Movies UK.

“And I don't say that just as a sales technique, it's like every time I watch it, I think ‘I don't know how we did that!’”

Guest starring Stephen Fry and Lenny Henry, the episode will see Jodie Whittaker returning as the Thirteenth Doctor, taking charge of the TARDIS once again alongside Tosin Cole (Ryan), Mandip Gill (Yaz) and Bradley Walsh (Graham).

Filmed in South Africa, the adventure sees the crew donning dinner jackets hinting at an espionage-inspired escapade, but beyond that, little is known about the episode or even what to expect from the rest of the series.

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Find out what we learned about Jodie Whittaker’s second season as The Doctor in our new interview with Chris Chibnall below.

Yahoo Movies UK: This is your second year in charge, and Jodie’s second year as the Doctor - did it feel like a difficult second album, or was it more like the comfortable twelfth album?

Chris Chibnall: It was neither. I think it was more of an exciting evolution.

It didn't feel like a different difficult second album at all actually. It felt like we had done what we wanted to in the first series and people had responded, more positively than we could have hoped.

SHEFFIELD, ENGLAND - SEPTEMBER 24: Jodie Whittaker (L) and showrunner Chris Chibnall attend the Doctor Who Premiere Screening at The Light Cinema on September 24, 2018 in Sheffield, England. (Photo by Dave J Hogan/Dave J Hogan/Getty Images)

Because the unknown of the response to the first series and to Jodie and to the idea of a female Doctor and all that kind of stuff, you know, you never knew how it was actually going to play out.

So I think we felt really thrilled about that, and so we sort of bounced into the second season. And I think the big thing for us is to take that sense of fun and enjoyment and energy and action and all the things we learned during the first series, and then go deeper into the things we enjoy doing and doing some new things and different things because I think that first series - Jodie's first series - was very much a jumping on point, an introduction for people who might not have known the show before, but obviously for people who had as well.

But it was making it very standalone... 10 episodes... pilot episodes... you would have heard us say all that when we were talking about it then.

Story continues

This year is different. It's like for everybody who joined last year, now let's go deeper into the world of Doctor Who, let's go deeper into the character of the Doctor, let's go deeper into the world of the companions.

So, it felt like a very natural progression. And the sort of thing we demanded of ourselves is okay: we’ve got to step it up, and we’ve got to go bigger and madder.

Did that mean you felt more free this time around to do what you really want to do?

I don't know about freer. I think in the first series we had a really specific intent, which was ten single episodes which would demonstrate the sort of range and breadth of Doctor Who. Lots of different stories and anybody could drop in any week, and that was very deliberate.

This year there are some two-partners, there's some serial strands going through. There's all kinds of little things for people to kind of pick up on and track through, while also keeping that sense of lots of different stories, lots of variety of storytelling. So you're taking what worked from last year and then you’re deepening it.

You always feel quite free on Doctor Who because you're starting with: where do you want to go in the whole of time and space? So if you're feeling quite restricted you shouldn't be there.

You made the last season in isolation - what was it like watching it being broadcast and has it changed how you approach the second series?

I don't know if it’s changed how I approached it. I think you end up in really weird situations watching this show because... so the first episode, I watched - this is not my doing this is somebody else is doing - but I watched at Madison Square Gardens in New York, as it went out live in front of 5000 people.

It would not be my preferred place to watch something that I've written with other people because I quite like to hide away. But it was incredible actually. I couldn't avoid being there because we were at New York Comic Con. And it was an amazing event. It was very emotional, actually, and I think what it just reinforced to me is the emotional bond that viewers and fans have with this show.

Ryan (TOSIN COLE) (BBC / BBC Studios) More

But what I felt was in that first episode - what I could feel in that room - and I think there was to a certain degree that then you could extrapolate that across the viewership, it's just the bond that people made with Jodie's Doctor and with those characters. They really connected and people just responded to her performance because it's so brilliant.

So I don't know what I learned from being in that room. I learned that the show can inhabit a lot of flavours within an hour, and that's great. And across the series.

What's different this time around how do we compare and contrast and specifically around the Doctor and her and her journey in the new season?

Last year, she is kind of showing these three new friends the universe. I think this year, she's going to face some big challenges, she's really going to need them.

That would be the biggest headline I think really. We also start off with a two-parter. We have a big two-part event to open the series I think it's fair to say.

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And that's not the only two-parter in the series. And there are various challenges for the Doctor coming through the series and also some returning monsters. We've got the Judoon coming back. We've also got the Cybermen coming back. And we've got some really fantastic scary new monsters as well.

There were no returning monsters really, last time...

No, we saved the Daleks for the special.

So was it a conscious decision that you wanted to bring returning monsters back, or was it just the natural thing to do?

I mean it was a sort of deliberate plan to not have any last year. To enable it to be about the Doctor and those companions, and also for them to be able to create their own adversaries.

It was always the plan in the second series, and also to make them feel rare and valuable and precious because they hadn't been around, so when you bring them back they feel a little bit more valuable and you’re just not bringing them out every year. Which is always the challenge in Doctor Who, to keep that balance really.

There are certain things that you want to see a Doctor go up against you know? And Cybermen would be another one on the list. So, yeah, it was very specifically planned that way, and as treats for the audience really.

Is there anything you can say about the Cybermen’s return, in terms of what to expect?

The Cybermen in Doctor Who S12. (BBC/YouTube) More

They’re pretty ferocious. I like that. And so, you said the opening opening storeys or two times.

Where do we find the team at that point when they come back in the opening story?

When we come back, probably a little bit of time has passed after Resolution. And they're on their travels really. As much as we saw them going off on their travels at the end of Resolution, they've been travelling together for a while, and they get pulled into an adventure at the top of episode one you'll be unsurprised to hear.

So, they're in a good place. They're a tight knit unit

And how has Jodie found her second year do you think she's more comfortable in the role?

The Doctor (JODIE WHITTAKER) (BBC / BBC Studios) More

The thing is with Jodie, she landed all guns blazing, I mean, both literally and metaphorically, on screen and off.

Even from her first audition, it was like ‘right, okay!’

So I think the thing that she's done this year... It's like she was amazing last year, and she was so Doctor-y, she had the essence of the Doctor right from the start.

And what you'll see this year is just that kind of deepening and broadening, and hopefully we've taken the 13th Doctor to places that she undoubtedly didn’t go in her first series.

So she does other things, there are other aspects of the character to explore this year. She's just limitless. And my job is to continually challenge her, provide her with material that we haven't given her before, and I think this series does that definitely.

In that sense, does she have an input into where things go in the second season?

Well it's funny. We sit down at the beginning of every series and I go, ‘these are the stories, these are the themes, this is the journey for the Doctor’ and we talk about that and she'll ask questions and then I'll also go ‘what are you interested in doing, what are you not interested in doing?’

So we have a general talk. And then it's sort of a dialogue. And then that will feed that into my thinking for the series and how we approach other scripts and talk to other writers about it, but it's a bit less verbal after that.

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It becomes me watching the rushes and seeing what she's doing, and sort of nudging and going, ‘oh she's really enjoyed that moment’ or ‘oh she's doing this and I didn't realise she could do that like that’ or ‘she's playing this differently’, which is really exciting.

So it's the sort of unspoken tennis match across the shooting in a funny way. I'll lob a scene and she'll hit it back.

So, there's a dialogue at the start and then there's not really a dialogue during the series, apart from everything she does, which I watch every day. And that's the joy of it: just thinking, ‘oh she did that brilliantly’. Okay, I've given you something new. Oh, she's done that brilliantly too. And you really can't ask for anything more from a lead actor, and I say that hand on heart.

She is extraordinary. I knew she was extraordinary having worked with her before. She's more extraordinary than I thought she was.

And your three supports: how have they found this second season?

Yaz (MANDIP GILL), Ryan (TOSIN COLE), The Doctor (JODIE WHITTAKER), Graham (BRADLEY WALSH) (BBC / BBC Studios) More

What you see with them is that thing of the first volume, if you like, they're just wowed by the journey of being with the Doctor, figuring out the Doctor, and the sheer variety of places they end up going to.

And then I think over time, naturally, as any kind of normal humans would do, is you’re starting to think, ‘who is this person and what are we doing?’ You can still be having a great time but you're going to start questioning what you're doing there, what the long term plan is, and who is that person?

Because actually, if you think of what she told them in the first series: It's pretty much zero.

I don't think I don't think she uses the word Time Lord, I don't think she uses the word Gallifrey in the first series. She might be using those words this year.

Are any other tweaks in the format that we should look out for? New costumes that sort of thing?

There's different varieties [of costumes]. I think the Doctor’s got a new scarf at one point. There's also, in the historicals, our gang get to dress up in historical costume as well.

I always love that.

I love that too! And you know we didn't really do it last year. And so we've got, two episodes where they're in proper historical pomp, and it's really great. You haven’t lived until you’ve seen Bradley Walsh in a top hat.

Can you tell us a little bit more about some of the supporting stars you might be coming in?

Lenny Henry, Stephen Fry, and Goran Višnjić all appear in the latest season of Doctor Who. (BBC/YouTube) More

Stephen Fry is coming in, he's with us in our premiere, as is Lenny Henry, he’s in there as well. We've also got Goran Višnjić from ER he's playing Nikola Tesla.

He’s really great. It was one of those where if there’s one person who could do this… and he said ‘yes’ straightaway! And it's a really brilliant script by a new writer Nina Metivier who co-created The A-List, she's written that episode, and it’s a brilliant episode.

It's making me laugh because I can see the monsters in my head. I'm like, ‘wait until you see those monsters’.

James Buckley as well from The Inbetweeners is in Episode Three. So that's just some of the ones we can tell you at the moment, but there's plenty more.

It's incredible because sometimes you write a part with somebody in mind and think ‘let's just go and ask them anyway’ and what's always amazing is that Doctor Who thing of people who go, ‘I've been waiting for you to ask my whole life!’

You know somebody like Stephen who was just over the moon to come and do it.

It blows my mind to think he’s not done it before.

Yeah, doesn't it? And actually, that's the joyous thing of my job, is you go ‘well, it's not right that this person hasn't been in a Doctor Who!’. The fact that Stephen’s not been in Doctor Who, and the same with Lenny [Henry] too.

These are great British icons, great British actors, so they’re both there in the opening two-parter and they're a treat, and they feel a treat on screen.

What can you tell us about the locations that you filmed in?

We've done quite a lot of foreign filming. Certainly episode one, I would say, is our most lavish, location-filled, action-packed episode, I think we've ever done.

And I don't say that just as a sales technique, it's like every time I watch it, I think ‘I don't know how we did that!’.

So we filmed South Africa, we filmed in various places across Europe. We try and do as much location filming as we can really because we were competing with some very big shows out there these days.

What other sci-fi and fantasy shows do you look to that you think are setting the benchmark these days?

Obviously at the moment Watchmen, which is extraordinary and is doing incredibly bold things.

You can never escape the shadow of Game of Thrones in terms of budget on screen, and ambition, and all that kind of stuff. Those would be the two, but there's just so much. Obviously now His Dark Materials on BBC One… the cost, and the scale, and the ambition... So, it's an amazing time for sci-fi and fantasy.

Are there any episodes that we should be looking out for that do things that we've never seen in Who before?

Yes, there are. I don't think I can say much more than that, because actually you never want an audience to sit down going ‘okay now we're going to sit down for the episode that's going to do something the show's never done before’. There are things scattered throughout the series that the show has not done before.

We're definitely still trying to push at the boundaries. We’re trying to do the familiar and the unfamiliar constantly, and the balance between the both of them. And I would say this series has absolutely hit both markers.

Doctor Who will return to BBC One on New Year’s Day with Spyfall written by Chris Chibnall, with subsequent episodes airing on Sundays