Rwandan-Scottish actor Ncuti Gatwa, 32, and Irish actress Nicola Coughlan, 37, are big fans of each other.
But at times, it's hard for the BAFTA and Scottish BAFTA award winners to describe what it was like working on the
, coming to BBC One and iPlayer, without sounding too cheesy.Gatwa became the 15th Doctor in 2023, taking over the TARDIS from Jodie Whittaker, the first female actor to play the part.
"It was so much fun working with Nicola. We are fans of each other and each other's work, and see each other out and about in London — I've always loved and respected her as an actor, " says the actor, who also played Eric Effiong in Netflix's
."We've always wanted to work together and so this was the perfect opportunity. It's quite tricky describing what it was like working with Nicola because everything just sounds like a bad pun - she was a Joy, she is a star, quite simply that.
"Working on the jungle platform with Nicola was precarious! The whole set was like a bucking bronco! It was mad to watch the crew have to reset everything after each take. Oh, that was fun.
"It was a set where you had to let whatever be, be, because everything was going to break, and not going to do what it was meant to do because everything was going to obviously fall. It humbled us all. The things we can do here are really cool."
Irish Film and Television Awards winner Coughlan, who played Penelope Featherington in Netflix's and Shondaland's period drama
and Clare Devlin in Channel 4 sitcom , feels exactly the same."Working with Ncuti was honestly wonderful. He is such an incredible talent, and you never know what it's going to be like when you watch somebody on screen and then get to work opposite them, but he's electric and talented in person too, if not more so. He has a real magic to him, and I think he's a perfect Doctor," says Coughlan.
"I really loved the prehistoric room of the Time Hotel. That was very fun, because it was extremely stunt-heavy. The two of us rigged up together, sliding all over the place, that was really brilliant. I loved filming those scenes."
titled 'Joy To The World', written by executive producer Steven Moffat, introduces Coughlan as Joy, who checks into a London hotel in 2024, only to discover that her quiet stay is anything but ordinary.
When Joy opens a secret doorway to the Time Hotel, she discovers danger, dinosaurs and the Doctor. But a deadly plan is unfolding across the Earth, just in time for Christmas.
Where has the Doctor been? What is going on in Joy's hotel room? An old enemy of the Doctor's is lurking in the wings and all of human history hangs in the balance. Can the Doctor save Christmas, everywhere, all at once?
"Joy is someone [who] comes across [as] very shy and retiring when you first meet her. She's somebody who never wants to cause a fuss, and it's a bit strange at the beginning because you see her checking into this hotel on her own on Christmas Eve and you don't really know what her story is going to be at this stage," says Coughlan.
"It seems quite unusual, and then you realise that she's somebody who is hiding a lot of pain and has a lot of struggle in her life, but is not really facing it. When she meets the Doctor, he's not somebody who is going to let her rest on her laurels and he really takes her through it. It's a big adventure.
"It's a huge honour. It's such an institution, so to be part of it at all is such a brilliant thing. I know how important the Christmas Special is to people. It's the kind of thing where the whole family will sit down at Christmas, even if they aren't regular viewers. Alex Pillai, who directed the episode, is such a huge Whovian and told us stories about him and his family watching it in the 70s. If I get to be part of that new memory for people, it's a big honour."
When Gatwa first read the script, he thought it was "beautiful" and "touching".
"Fighting a T-rex and working with Nicola Coughlan, Jonathan Aris, Steph de Whalley and Joel Fry was great fun!" says Gatwa. "It was a really great cast and a really beautiful touching script. I was excited for the character development for the Doctor in this episode; I thought, 'This is good for you, you need this!'",
"It feels very nice to be back with a Christmas Special. It's got such a joyous, lovely, warm Christmassy feel. There is so much heart in this story which touches on loss, love and humour, which is exactly what you want for a Christmas Day adventure with the Doctor. I can't wait for the audience to see it, it's very joyous."
But Coughlan admits she was initially mystified: "I just loved it so much, aside from being completely confused by the timeline at first when marking up my scripts! You also often film things out of sequence so there's already elements of time travel in filming any show, and then you put in the actual Doctor Who time travel and you're thinking 'Oh my god'. I just thought that this is really fun, and it's so different to anything I've ever done before. I was super excited to do the stunts, which are a thing that I didn't know I would enjoy. The chance to do those was brilliant."
"I think it's the perfect family show, because it's funny, it's heartfelt and it's adventurous. It's just pure excitement, and joy, and I think this episode in particular has a really beautiful message underpinning it which is all down to Steven Moffat's writing. It's a perfect cocktail of all those things."
- , 'Joy to the World', comes to BBC One and BBC iPlayer on Christmas Day