'Slow Horses' Star Reacts to Episode 5's Most Harrowing Moment: "You're in a Horror Film"

Editor's note: The below interview contains spoilers for Slow Horses Season 6 Episode 5.

With only one episode left, Slow Horses Season 6 has crossed into surprising new territory, with the Apple TV spy thriller emphasizing that there's always more at play than the team at Slough House even know about. As the threats against MI5's biggest misfits continue to mount, Jackson Lamb (Gary Oldman) is closing in on Damien Cantor's (Harry Lloyd) ties to everything while almost everyone else hunkers down at none other than Diana Taverner's (Kristin Scott Thomas) vacation house. Meanwhile, River Cartwright (Jack Lowden) stops at nothing to rescue Sid Baker (Olivia Cooke) from the clutches of Russian assassins Jim (Kyle Soller) and Jane (MyAnna Buring), but no one is getting out alive without some serious bumps and bruises.

Episode 5, "Sayonara," is already teeing up a big-time showdown in the finale, but it actually starts with a brutal twist for one of Season 6's deadliest threats before the opening credits roll. Before premiere, Collider spoke with Soller about building Jim and Jane's complicated relationship with Buring (even in their scenes without any dialogue), why he and co-star Tom Brooke went back to Mick Herron's Slow Horses books for their brutal bathroom fight in Episode 4, why Jim's ultimate showdown with River and Sid feels more akin to a horror film, and more.

COLLIDER: Something that really stands out in your scenes with MyAnna [Buring], especially when Jim and Jane are alone and talking in private, is that it feels like there's a closeness that goes beyond professional colleagues. How did the two of you work to build in more backstory so we feel the depth of that relationship beyond just two assassins working together on the same mission?

KYLE SOLLER: MyAnna and I were really interested in pursuing something that was much more three-dimensional than what's written in the book, even though they're kind of wonderfully strange characters, and [director] Adam [Randall] was very supportive, and [showrunner] Gaby [Chiappe], as well. We wondered if there was this unspoken but acknowledged “I'm kind of into you,” but in a kind of teenage way. “Are you into me? I don't know.”

Also, there's a contrasting devotion to what they're doing. Jim, while he seems much more up for playing the game of dressing up and creating all these elaborate scenes of people dying “by themselves,” he actually is just so happy to be in the UK and to experience the strangeness of a hardware store off the North Circular. But he actually isn't in it for the long run because he's found, potentially in Jane, a reason out. Jane is much more conflicted in that she is hard-lined to the end.

MyAnna and I work really similarly in that we're looking for points of tension and contrast within our characters, in the scenes that we're in. I like to see people under pressure, and then, when you see them together, there is this kind of lived world, so they're not just these Terminators who show up. We've seen that so many times.

I do have a bone to pick with you, because this season resulted in the death of someone very near and dear to my heart on Slow Horses in Coe...

SOLLER: You’re preaching to the choir. [Laughs]

Kyle Soller Breaks Down His Brutal Bathroom Fight With Tom Brooke in 'Slow Horses'

"I see you, and maybe in another life we could go for a beer at the bowling alley and play some air hockey."

Image via Apple TV

The build-up to Episode 4's fight between the two of you, the conversation you have at the sinks, says so much with very little dialogue. Maybe Jim and Coe don't want to go through with this, but there's an acceptance of the inevitability of the moment. Did you and Tom [Brooke] talk about how to tackle that scene together, knowing what it's going to inevitably culminate in — with only one character walking out of there alive?

SOLLER: I'd been a fan of Tom's for a long time, and we're friends. We really wanted to explore these two people who are devoted to these institutions and caught up in the machinations of other people's choices and orders, being presented with this very real situation of having to kill someone else, but the conflict of not really wanting to go through with it.

Tom went back to the text that Mick [Herron] wrote and came up with a version of the scene, which we worked on together, and then we presented it to Gaby and Adam, and they thought it was great. Tom and I are similar in that we're always looking for a little left hook in a scene, or something a bit weird. And Coe is such an incredible character, and it's such a pivotal moment that I think it was really cool to present a very naked, like, two guys meeting in a toilet, but who see each other, and, as you say, are resigned to the fact, like, “Ah, we're on the train track, and we're not getting off at this station. We have to go forward.”

There's also a lovely nod to Coe in Jim going, “Is that a push knife?” So there’s respect. “I see you, and maybe in another life we could go for a beer at the bowling alley and play some air hockey,” like we did when we weren't filming. And that created, I hope, another level of tragedy for Coe once he goes, because you see how he's been used by the system, and it creates a level of humanity for Jim, with him going, “I don't even know how to get out of this anymore. Somebody will come kill me if I don't kill you right now.” It's very cool.

As we know, once the Slow Horses get involved, nothing goes according to plan. With Jim and Jane, as much as they're trying to keep things tidy, it gets increasingly messy. The situation goes sideways once they take Sid, too, although we see the outcome of that in the penultimate episode. I have to ask about filming how everything wraps up for Jim, who meets his demise at River and Sid's hands. It looked very cold, very wet, and very unforgiving.

SOLLER: Those three things. [Laughs] Tick, tick, tick — cold, wet, and unforgiving, which I think you probably could say about the entire season. Those are the bullet points, which is quite right because it's a huge climax — well, sort of a pre-climax, I guess, before the last episode.

But it was amazing because it enters into this other territory where, from the service station, you're in a horror film, with the classic run through the woods. The stunt team was incredible, and the fight direction was amazing because it was just psychologically truthful about people who were completely at the end of their tether and just trying to get something done and fight for their lives, and messy and very cold — I had on so many different layers of things underneath my clothing.

But it also felt really cool because, in terms of River and Sid, him rescuing her, finding each other again, the whole grief that he's been carrying from his grandfather. You have Jim's grief of thinking Jane has just died as he's trying to kill Sid and drown her in the lake, and looking at the swans. It's this other moment, I think, in the whole season. It really feels like a little short film, almost. Yeah, it was wild. It was hard, but really great.

Kyle Soller Lists Off His Favorite 'Slow Horses' Season 6 Moments

"I basically loved every bit of action that MyAnna and I did as Jim and Jane..."

Image via Apple TV

You and MyAnna get to do a lot of really fun stunt sequences this season. Is there any scene that stands out in your mind that you just really loved doing from start to finish?

SOLLER: The bowling alley was amazing, because the way that Adam was shooting it, it almost felt like Jurassic Park, with the raptors hunting the children. The visual nature of all the neon and stuff, the retro styling of that place, was so perfect, just a time capsule.

I basically loved every bit of action that MyAnna and I did as Jim and Jane — gunning the Jeep around the farm, but specifically the bowling alley. The fight with Tom was amazing. We did that in the studio. And then the fight with River and Sid; there was such a momentous feeling about doing that scene and getting it right, making it sloppy and messy. I also loved having fun in the hardware store.

There's stuff that's been cut, portions of a scene that MyAnna and I had shot that I think give too much away because we're sort of wrangling with, “We've got to do our job, but why are we here? What's going on? This is bullshit. It’s too easy.” All of this stuff, and trying to unpack our relationship and our duty as Russian agents. And I understand that's probably been let go so that you don't really know who these people are attached to. You think they might be attached to Harkness, or Damien Cantor. So, I get it, but I had such a great time, from crafting the relationship with MyAnna to playing air hockey in a retro bowling alley.

New episodes of Slow Horses Season 6 premiere Wednesdays on Apple TV.