Slow Horses: Behind The Scenes Of Season Four with the Cast and Creators

Slow Horses is a darkly humorous espionage drama on Apple TV+ that follows a dysfunctional team of British intelligence agents who serve in an MI5 dumping ground department known unaffectionately as Slough House. It’s a television series based on the Slough House series of novels by Mick Herron and adapted by Will Smith. It follows an MI5 unit where failed agents are consigned, under the supervision of Jackson Lamb (Gary Oldman).

Executive producer Doug Urbanski is here, along with four standout cast members: Saskia Reeves (Standish), Rosalind Eleazar (Louisa), Jonathan Pryce (David Cartwright), and Gary Oldman, who leads the ensemble as the irreverent and enigmatic Jackson Lamb discuss the show.

A Movie Star’s Leap into Long-Form Television

Gary Oldman is a name more often associated with big-screen blockbusters and Oscar-winning roles in films like Mank and Darkest Hour than serialized television. So what drew him to this particular project?

“I’ve always been a fan of long-form TV,” Oldman explains. “There’s a unique depth you can explore when you live with a character over several years. When Slow Horses came along, the scripts were excellent, and Mick Herron’s novels are just fantastic source material. Add to that this extraordinary team—I couldn’t say no.”

Portraying Jackson Lamb, a foul-mouthed, chain-smoking intelligence officer with questionable hygiene and zero patience, has become a defining role for Oldman. “He doesn’t really conform to social norms,” he laughs. “But I think a lot of that persona is deliberate. It’s his armor. He uses it to keep people at bay.”

Lamb isn’t a character that grows or transforms in the traditional sense. “He’s fairly set in his ways,” Oldman admits. “But what changes are the situations—each season brings a new crisis, a new puzzle to solve, and that’s where the character’s complexity really shines.”

Season four opens with a bombing that detonates personal secrets, rocking Slough House’s already unstable foundations.

From Page to Screen: Crafting the World of Slough House

Executive producer Doug Urbanski was instrumental in bringing the series to life—and in bringing Oldman on board. He shares how it all began with a simple conversation in his living room.

“Gary told me he wanted to do something where he could use his real voice, no prosthetics, no heavy costumes. I said a little prayer, and not long after, I got this script,” Urbanski recalls. “We were flying to Venice for a Soderbergh movie, and I started reading it. I turned to Gary and said, ‘I think I’ve found your new best friend. His name’s Jackson Lamb.’”

Initially, Apple TV+ envisioned just a three-episode adaptation of two books. But Urbanski and the team pushed for more. “We wanted to do twelve episodes per year, split into two seasons of six episodes each. That way, we preserve the depth of the novels while creating binge-worthy arcs for viewers.”

To maintain cinematic consistency, each season is directed by a single filmmaker. “It’s like creating a six-hour movie,” Urbanski reveals. “It’s a huge commitment for any director, but it gives the show that seamless flow.”

The production also adopted several strategic choices—like ensuring a new season drops within 12 months and ending each with a tantalizing teaser for what’s next. “We want viewers to know their time investment would always be rewarded.”

Character Chemistry and Creative Collaboration

One of the strengths of Slow Horses is its ensemble cast—a tight-knit group whose chemistry has grown across four seasons. Jonathan Pryce, who plays David Cartwright, describes the richness of the experience.

“Each season offers new dynamics, new emotional challenges,” he says. “I’ve spent much of the earlier seasons working separately from the rest of the cast, often just with Jack Lowden’s River. But this season, I got to step into the Slough House set for the first time. I felt like a kid in a toy store—it’s such an immersive environment.”

Pryce, like many cast members, chose not to read the books before diving into the role. “I wanted to stay true to the script. The writing is so strong, and I think there’s a certain freedom in discovering the character as the audience does.”

Rosalind Eleazar, who plays Louisa, echoes that sentiment. “I’d never done a series that ran six seasons. It’s been amazing watching Louisa evolve. She starts off combative, but there’s real vulnerability there too. And as her relationship with River deepened, it gave me even more to play with. It’s been a privilege to grow with her.”

She also praises the collaborative nature of the production. “We really do have a say in where our characters go. It’s not just handed to us. We discuss arcs, motivations, relationships. It feels like we’re building this world together.”

Saskia Reeves, who plays the ever-dependable Standish, says it was the role of a lifetime. “She’s such a mixed bag—smart, tough, deeply emotional. From the start, I knew this character would be a gift. The scenes with Gary are especially rich. We have this complex, layered relationship that’s so fun to explore.”

Inside Slough House

Slow Horses may not boast the opulence of a period drama like The Crown, but its attention to detail is noteworthy.

“The first time I walked onto the Slough House set, I was floored,” says Reeves. “It felt like stepping into a real office—right down to the cobwebs. The set is a character in itself.”

Oldman agrees. “You might think modern costumes and sets are easy, but a lot of thought goes into every sweater, every tie. You don’t just throw on a coat. It has to feel right for the character. We work closely with costume designers, sometimes walking through shops together to find the exact right piece.”

Despite its contemporary setting, the level of craftsmanship is on par with any historical epic. “There’s a tendency for awards to overlook modern design work,” Oldman notes. “But the truth is, it’s just as demanding—and just as deserving of recognition.”

New Season of Slow Horses

With nine Mick Herron novels now in print, the source material for Slow Horses shows no signs of drying up.

“Ultimately, we’ll go as long as the stories stay strong,” Urbanski confirms. “The key is honoring the characters and keeping the bar high.” And if Apple keeps writing the checks? “We’ll keep making them,” he added with a sly grin.

The cast, too, seems more than ready to continue. “This has been one of the highlights of my career,” Oldman adds. “The role, the writing, the people—there’s magic here. You don’t walk away from that lightly.”

As we head into Season Five, fans can expect more of what makes Slow Horses great: razor-sharp dialogue, morally gray characters, high-stakes plots, and that gritty, unforgettable London backdrop.

But most importantly, they can expect a show that never loses sight of its heart—the flawed, fiercely loyal, and completely human team at its core.

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by Staff Writer

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