“Slow Horses” has quietly become one of the most consistently delightful shows on television. Five seasons in, the Apple TV+ spy series remains genuinely suspenseful without losing the very British sense of humor that has distinguished it from the beginning. This past season was one of its best, raising the threat level with some of the series’ most unsettling storylines while giving Christopher Chung’s hilariously self-assured Roddy Ho considerably more time in the spotlight.
Much of what makes those shifts work comes down to an exceptionally well-cast ensemble. Led by legendary casting director Nina Gold, with Melissa Gethin Clarke stepping up to co-cast the series beginning with Series 4, “Slow Horses” has assembled actors who can move between comedy, drama and action without disrupting its unusual tone. Clarke, who previously worked as an associate on the series, has now earned her second Emmy nomination for “Slow Horses,” the show’s third nomination for casting.
Giving Roddy a girlfriend should probably have been the first warning sign this season. His relationship with Tara, played by Hiba Bennani, becomes part of a much larger story that eventually connects to some of the season’s most frightening moments. At the same time, putting Roddy at the center of so much of the action allows Chung to take a character who has often been one of the show’s funniest supporting players and prove just how much more he can carry. It is a testament to the depth of the ensemble that expanding a supporting character’s role feels like an opportunity rather than a detour.
Of course, Gary Oldman has become so inseparable from the disheveled and frequently disgusting Jackson Lamb that it is difficult to imagine anyone else playing him. But building around an established ensemble presents its own challenge, particularly as characters leave and new faces enter Slough House or orbit its world each season. “There are usually guests who come in every season, and they have to fit in with our slow horses,” Clarke tells Awards Focus. “It has to make sense.”
Season 5 put that philosophy to the test with several additions, including Bennani as Tara, Nick Mohammed as London mayor Zafar Jaffrey and Bilal Hasna as his son, Irfan. Tara and the other characters connected to the season’s Libyan storyline required an extensive European search, with Clarke and Gold working alongside Libyan advisor and Arabic dialect coach Khaled Abunaama to find actors who could handle the specific dialect while preserving a mystery that depended on audiences not immediately recognizing how the characters were connected. The team also had to consider whether someone as recognizable as “Ted Lasso” star Mohammed could disappear into the world of “Slow Horses” without distracting from it.
For Clarke, the first requirement remains deceptively simple: find great actors who understand the show’s very particular tone. “It can be really thrilling, it can be dark, but it is so funny and sharp and very British,” she says of Will Smith’s writing. That instinct has also allowed longtime ensemble members such as Aimee-Ffion Edwards to grow with their characters, with Clarke noting that every Slow Horse eventually gets a chance to move closer to the center of the story.
Awards Focus spoke with the Emmy-nominated casting director about stepping up to co-cast “Slow Horses” alongside Gold, finding the right actors for Season 5’s Libyan storyline and why Roddy Ho’s unlikely romance required its own approach to chemistry. Clarke also discussed casting Mohammed against audience expectations, watching longtime ensemble members grow into their roles, the importance of authenticity and why, after years of learning from Gold, she believes so much of great casting ultimately comes down to taste and trusting your gut.
Awards Focus: First of all, congratulations on the Emmy nomination. What was your reaction, and where were you when you found out?
Melissa Gethin Clarke: This is the show’s third casting nomination and my second. I stepped up to co-cast with Nina, and I was an associate before I started co-casting from Series 4. Last year was quite a shock because it was the first one.
This time, I was with my assistant and completely forgot that the nominations were coming out because I’d set the time wrong on my phone. I got a text message from Christopher Chung, who plays Roddy Ho, saying, “Congratulations.” So that was very nice and very surprising. It’s really amazing to be nominated.
AF: You bring up Christopher and Roddy Ho, and this past season we get a lot of Roddy Ho, which is a delight. When you were casting Tara, his love interest, what were you looking for? The moment Roddy has a girlfriend, it almost has to raise suspicions.
Clarke: She had to be so many things. When we got the scripts, we’d already read the books beforehand. The scripts are based on the books and are fairly faithful, but this season changed a little bit more than we normally would.
In this season, these characters are Libyan, so there was quite a lot of discussion around that because Tara and the three men are connected. We didn’t want the audience to know straight away that the two storylines were interconnected. We had to figure out a way to do that, and the way we decided was to have them be Libyan but also from somewhere else, just to make it more complicated for ourselves.
They also had to speak Arabic, and a very specific dialect of Arabic. We had an incredible Libyan advisor, Khaled Abma, who’s an amazing Arabic consultant, dialect coach and voice coach. He worked with us right from the beginning of the audition process because the people we ended up casting are from different parts of the Arab diaspora across Europe.
Hiba is French Moroccan, and she hadn’t done anything quite this big in English before. She had to speak fluent English and Arabic, be able to do that dialect of Arabic, be incredibly beautiful and also be an amazing actor. It’s such a complicated role because she has to convincingly be this kind of innocent ingénue, but she’s also quite terrifying when she flips. She can do that switch so well.
It was also really fun to imagine the kind of woman who could trick Roddy Ho. I mean, I think a lot of women could trick Roddy Ho. (Laughs.) But the fact that she’s so beautiful and charming means everyone’s alarm bells are ringing, except Roddy’s because Roddy thinks he’s an absolute stud muffin. It was fun, but it was challenging.
AF: With a relationship like that, would you normally do a chemistry read? How do you make sure the dynamic between the actors is going to work?
Clarke: In a normal circumstance, and certainly for other relationships on “Slow Horses,” we would do that. We did discuss it, but then we realized the whole idea is that they’re not meant to have chemistry. (Laughs.)
Roddy is meant to think this is the love of his life and not think anything is wrong with it. So we didn’t do one for this. We decided to cast Tara on her own and then put them together. In the end, they have their own special kind of chemistry. But normally, in that situation, we would.
AF: Listening to everything you needed from Hiba, authenticity comes to mind, which isn’t necessarily something people immediately associate with a show that can also be very funny. How important is authenticity to you, and how consistently is that applied across the casting of “Slow Horses”?
Clarke: It’s very important to me. Authenticity is incredibly important. We should be casting properly when you’re given a really specific reason for a character to be from a certain place.
In this case, their background is that they are disgruntled with the British government because of what the British government did in Libya. It’s an absolute no-brainer that, of course, they have to be authentic. It’s a big undertaking, and you do your very best. Libya is a small place, and we do have an actor who lives in the UK and is from Libya who’s one of our lovely new cast members in Series 5. But we try our very best to be as authentic as we possibly can.
I think that adds a level of realism. We’re generally really spoiled on “Slow Horses” because it’s set in London, and we always say that London is like a character in the show. The joy of casting something contemporary that’s set in London is that you get all the flavors of London. London is this huge mixing pot, like New York or L.A., this amazing mixing pot of cultures.
We usually have a lot of freedom. It’s important to us, including within the security services, to make it look like London looks and feel like London feels.
AF: Then you bring in someone like Nick Mohammed, who’s very recognizable from “Ted Lasso.” Do you ever worry that a familiar face could be distracting, particularly when you’re asking audiences to see that actor in a very different light?
Clarke: Yes, I guess that is a consideration. Again, we have this freedom on “Slow Horses” because we have Sir Gary Oldman, Dame Kristin Scott Thomas and Sir Jonathan Pryce, and then we have these real up-and-comers who are very well known but weren’t quite at that level when they started.
When it comes to smaller roles, everyone wants to be in “Slow Horses” now, which is absolutely lovely. But we were casting Series 3 before Series 1 and 2 had come out. I think we were nearly shooting Series 3 before anything had come out. There was a time when that wasn’t the case, but now we’re very lucky.
With someone like Nick Mohammed, yes, there’s always a little bit of, “We don’t want it to be distracting.” There is a real realism to the show, and we’ve very rarely brought in someone who is a very recognizable face. We’ve had Hugo Weaving come in.
But with Nick, I suppose for an American audience, yes, Nick is from “Ted Lasso.” For us, we’ve been seeing Nick do comedy for 10 or 15 years. Nick is the most incredible, clever comedy actor. He does character comedy. He came up through university doing comedy, and he has a character called Mr. Swallow. He’s really, really clever.
That’s the joy of casting. You get to put someone in a role because you’ve seen them in theater and you’ve seen them do all these different things that maybe a global audience hasn’t seen. I’m delighted that Nick is so well known now because of “Ted Lasso.” He can do lots of things.
AF: “Slow Horses” has such an interesting tone. It’s a spy thriller that can be genuinely dark and then suddenly very funny. What tells you that an actor can pull off that balance?
Clarke: It is a very specific tone. I guess that’s something Nina has really instilled in those of us who trained under her: the naturalism in a performance. The most important thing is that they’re a really great actor, and then we get into tone because not everybody can get that tone.
Will Smith’s writing is exactly what you say. It can be really thrilling, it can be dark, but it is so funny and sharp and very British. There is a really specific kind of actor.
Again, we’re spoiled by the fact that the show is out now. People can see it, watch the episodes and get that tone. But that quintessential British comedic tone, not everybody gets it. That’s why you get people in the room, play around with it and try it in different ways.
When it clicks, when you have an actor come in and they totally get the tone and land those lines in a way that maybe you hadn’t even thought of, it’s kind of gorgeous.
AF: Of the new characters this season, which was the most challenging role to cast?
Clarke: The Libyan characters were definitely the most challenging logistically. We were really determined to get it right. We wanted Arabic speakers listening to understand that these people were speaking a Libyan dialect. All of that creates a real challenge. It’s difficult to make sure you’ve got it right.
It was a big process, and it took months. We had a lot of in-person auditions. Hiba was based in Paris at the time. I think we had her over two or three times, recalling her and working with dialect coaches. We were really determined to make sure we got it right.
In the end, she did an incredible job, and I’m so glad all that work was worth it. But it is a lot of work. We did a huge European search for all of those characters because you want to make sure you get it as right as you possibly can.
AF: You mentioned the mix of established legends and up-and-coming actors. Over your years on the show, whose performance has really amazed you as you’ve watched them grow into these characters?
Clarke: It’s really gratifying. That’s something that, the longer my career goes on, I’m starting to experience more. I’ve been doing this about 12 years now, and it’s getting to the point where kids that you cast are now grown-ups in their late twenties. That’s quite alarming. It makes me feel really old. (Laughs.)
So many of our “Slow Horses” actors have been around. Aimee-Ffion Edwards, for example. I came on at the end of Series 1. Aimee-Ffion Edwards joined with Kadiff Kirwan as new horses in Series 2. She has been a regular on British television for years. She was in “Peaky Blinders.”
Her performance in this is absolutely exceptional. She’s a really well-known face in British television, but to see her reach this global audience and enjoy the stuff she has to do in Series 5, I think she’s amazing.
Yes, this is a Roddy Ho season, but every single horse gets their time. That scene in the bathroom of the nightclub with Jack Lowden, where she’s run away and tells him how much she misses Marcus, and then that flip into, “Oh, I fooled you.” The emotion behind her eyes is incredible.
I think she’s the most incredible actor. To get to see her season on season, I don’t know how they get better every year, but they do. All of our slow horses really inhabit their characters. They know exactly what their characters would do at this point. Watching them work is an absolute joy. They really are phenomenal.
AF: You’ve mentioned Nina Gold several times. As you’ve grown from associate to casting director and co-casting the series with her, how much of casting is technical skill versus gut instinct?
Clarke: Things are a deal breaker until they’re not, right? (Laughs.) That’s kind of the joy of it and why I think our job is so creative. It is about taking risks. It’s about knowing what people can do and having that gut feeling.
I have this thing where people say there’s “perfect casting,” and an actor can portray a role in a way that is perfect. You watch the show or film and think, “My God, no one else could have done it.” And that’s true. No one else could have done it the way they did it.
But because we come onto a project at such an early stage, there were so many different versions of that character. Everything was open. The possibilities were endless. Another actor might have done an incredible version, but it would have been different. That would have been a different show. This is the show that we’ve made, and isn’t it wonderful?
Quite a lot of it is gut, and you can’t teach taste, I guess. I’ve been trying to pick up as much as I can from Nina in all the years that I’ve worked for her. She has absolutely incredible taste. I think that’s her reputation. I do think she’s the best casting director working today. I’m absolutely honored to have worked under her for such a long time. She’s an incredible mentor.
But you can’t exactly teach someone taste. I think your taste is your own, and then you’re informed by the conversations you have. It was really lovely to be co-casting with someone like Nina, to hear her insight, agree on certain things, have different opinions and have a conversation about it. It’s really creatively fulfilling.
So much of it is gut. Ultimately, you have to take the risk and go with your gut. If it works, that’s amazing.
AF: Casting is getting more awards recognition, including the new Oscar category. As a voter yourself, what do you look for when evaluating casting? With “Slow Horses,” for example, Gary Oldman was cast years ago, while you’re continuing to build around that original ensemble.
Clarke: I always think about ensemble. When you’re voting for other casting directors and watching these incredible ensemble pieces, sometimes it’s because of a certain performance, but mostly it’s because of the way the performances all meld together, make this world and pull me into it.
As a casting director, I know how hard it is to have an ensemble that just works. When it works, it’s wonderful. So I look at that. I think about ensemble.
I agree with something like “Slow Horses,” where that original ensemble was set. But some people have left and some people have come in. It’s not entirely the same ensemble it was in Series 1. There are usually guests who come in every season, and they have to fit in with our slow horses. It has to make sense.
That’s always a challenge, and it’s something I think about when I’m watching and voting for subsequent seasons of things. I look at the way other casting directors put together an ensemble cast. I’m so inspired by the work. I think they’re absolutely incredible, and I know how much work goes into that.
AF: There’s so much animosity among these characters, even if much of it is playful. What is the atmosphere actually like among the cast off screen?
Clarke: They’re like a big family. I actually go to set more than I normally would for any other show because I’ve been on it for such a long time. It’s been five years now, five years and seven seasons, so I do go quite a lot.
They’re like a big family at this point because of the shooting schedule. We shoot two series back-to-back, so they’re generally shooting for something like 10 months out of every 18. They spend a lot of time together.
They have a real family dynamic. It’s lovely to see them interact with each other that way on and off screen. It’s an added bonus. We’ve had the same crew for nearly all of it as well, so everybody knows everybody, which is very unusual.
AF: Was there anyone who came in this season and ultimately gave you something different, and even better, than what you expected during the casting process?
Clarke: I guess Bilal Hasna, who we cast to play Nick Mohammed’s son, the son of the Mayor of London. He’s a green activist who blows up an energy plant early in the season.
We auditioned a lot of people for that. It wasn’t a huge role, and Bilal’s star has been on the rise. He’s doing some incredible work, and we were really overjoyed that he wanted to do it.
Then he completely inhabited that role. Just the animosity between him and Nick Mohammed, I looked at them and thought, “My God, of course you’re father and son.” I don’t know why I’m so surprised because we cast them that way. (Laughs.) But he’s just such an exciting young actor, and I’m always excited to see what he does with something, no matter the size of the role.
That’s something we’re very lucky with on “Slow Horses.” The writing is incredible, and actors, especially in the UK, are looking for great writing. That’s what they’re always looking for. Bilal took a role that could have been a small role and really made it into something memorable, which I think is amazing.