On the surface, a film set primarily in one hotel room with a pair of actors might seem simple. But in the case of “Good Luck to You, Leo Grande,” which premieres Jan. 22 at the Sundance Film Festival, limiting the location gave the film an opportunity to explore what star Emma Thompson calls “the emotional landscape.”

Thompson plays Nancy, a widow and former teacher who has stepped outside her comfort zone for the first time in her life and hired a sex worker, the titular Leo Grande, played by “Peaky Blinders” actor Daryl McCormack. With a script by Katy Brand and direction by Sophie Hyde, what unfolds is a frank, funny and touching adventure as these two very different individuals get to know one another and themselves a little better.

Variety spoke with Thompson, McCormack and Hyde about putting together the film, which was shot in 19 days. Says Thompson with a laugh, “Sometimes I look back and think: ‘How the hell did we do that?’”

Emma, how did this script come to you? I believe you’d worked with the writer before?

Emma Thompson: Yes, she was in my second “Nanny McPhee” and she’s a wonderful writer and woman. She sent me this and said, “I’m trying to get this made.” And I read it and just said, “You have to do this. And please, please let me be in it!” Because it was so funny and so ready. It wasn’t like I read it and said, “This is a germ of an idea that needs work.” It was doable. Though she and Sophie still worked quite hard on it before we started.

Sophie for you, was Emma already attached before you signed on?

Sophie Hyde: Emma was on board before Katy and Debbie Gray, the producer, came to me. The idea and Emma Thompson as a combination was just irresistible. Like there was no way I wasn’t going to do that. Like, I wanted to see Emma in this role. And if I wanted to see it, I felt other people would want to see it for sure.

Daryl, when the script came to you, Emma was already attached. Was that exciting or intimidating or —

Thompson: Horrifying! (Laughs)

Daryl McCormack: Well, it was kind of funny because I was told by my agent to read this script and the letter said Emma Thompson was attached. As I kept turning the pages, I was like, “Wait, I think there’s only two people in this movie!” I mean, I’m still kind of relatively starting off in my career so to be even be considered to hold a film with someone like Emma was unfathomable. I couldn’t believe it.

Was there any kind of chemistry read together?

McCormack: Not a chemistry read as much as we hung out one afternoon and went for a walk. We spoke about the script, it’s message and just how much we were in love with it. That was kind of the process. And then shortly after that, Emma texted me saying, “I’ll see you on set.” And I couldn’t believe it – I had to make sure she didn’t mean to text someone else and sent it to me on accident!

Thompson: And I have to say, he was up against some unbelievably great talents so it’s all the more of a testament to his talent. There was something about Daryl’s curiosity and his gently inquiring nature that reminded me of Leo. It’s one of Leo’s best qualities and probably one of the things that makes him a great sex worker.

Hyde: Leo could have gone in so many different directions but Daryl brought something to him so specific, he had a gentleness and emotional accessibility that I found thrilling. He brought layers upon layers to Daryl. And he’s standing up with one of the greats and he had to meet her. And he did.

This film features two people in one location. But that brings about all sorts of other issues and forces you to be even more creative. Did you find it challenging?

Thompson: I found it one of the most satisfying professional experiences of my life because it was, in a way, the purest form of acting you can do. One space, no props. There’s nothing to do. It’s Peter Brook time. It’s as pure as it gets. The landscape is the emotional landscape. Obviously it’s an intense experience but also one full of sheer joy.

Hyde: I got excited by the idea of two actors in one space, because it gives me space to explore the things I’m interested in – which is two human beings interacting. Of course then you wonder how can we keep this interesting? How will we maintain this as a piece of cinema? So we started working towards answering that question pretty quickly.

Sophie and Daryl, did you speak with real sex workers to help inform the character of Leo? Were you able to talk to people in the same line of work?

McCormack: I was given a list of sex workers to speak to that was compiled by Sophie. I think her aim was to find the sex workers who really see their work as a vocation, because we felt that’s where Leo sat. They were such inspiring people with such power and autonomy over their lives. Their spirit really rubbed off on me and I hopefully carried that into the film.

Hyde: For me, it was really important that I had a lot of conversations and read a lot of stuff with people who had a lived experience of sex work. And we had some incredible consultants that really helped us to build the character of Leo and gave us so much insight into the really varied experience of people who participate in sex work. I think there’s a huge range of people working in sex work. But I also think it’s really lovely to be able to portray a character that is doing it and is good at it and wants to offer something to another human that is really deep and interesting. You know, I think we see so much sex work on screen, and it’s really problematic. It’s the “Pretty Woman” idea that people are going to fall in love or it’s the story of how it’s dangerous, when any industry can be dangerous when you’re interacting with humans. So I really enjoyed being able to tell this story but I needed to work with people to make sure that what we were presenting felt true and to get the layers of this character.

Emma, was Nancy difficult for you to access or do you feel you knew her pretty well even before filming started?

Thompson: I’ve always known Nancy. I know the history in this country, particularly, of the puritanical responses to sex. The inability to talk about it, or recognize it’s difficult nature. The conversations that exist around sex in my culture are either depressing, or just not very inspiring. I’m sure she’s not uncommon – a woman of 62 who’s never had an orgasm, even on her own. And I think it’s not uncommon in many cultures, because female pleasure is disapproved of in most religions, and most moral structural setup; it’s absolutely fine for women not to feel pleasure. And not to have appetites of any kind. It’s preferable, really. We’ve got a history of repressing pleasure, and in particular history of repressing sex, repressing female sexual pleasure. So, Nancy, I think, is very normal.