Gaby Chiappe has taken the helm as head writer for the sixth season of the critically acclaimed espionage series Slow Horses, stepping into a role that carries considerable expectations. The series, which streams on Apple TV, follows a group of MI5 operatives consigned to Slough House—a holding area where agents sidelined for mistakes or misconduct find themselves effectively exiled. Since its debut in 2022, the show has garnered international attention for its blend of dark comedy and thriller elements, anchored by Sir Gary Oldman’s portrayal of the irascible Jackson Lamb.

Chiappe, a seasoned television writer with nearly three decades of experience, emphasized the importance of preserving the tone that fans have come to expect. “I definitely didn’t think ‘I’m going to do this differently’,” she said, underscoring her goal to maintain continuity for viewers. She acknowledged the challenge of filling the shoes of the previous showrunner, Will Smith, noting the responsibility to ensure the transition did not alienate the audience.

Central to the series’ appeal is its distinctive voice: sharp, often explicit dialogue and a cynical, yet humorous, outlook on British intelligence and bureaucracy. Jackson Lamb’s acerbic wit and gruff demeanor are especially highlighted, with Chiappe praising Oldman’s performance as a decisive factor in the show’s success. She described Lamb as “always the cleverest person in the room,” whose unpredictability keeps viewers engaged.

Adapting Mick Herron’s novels to the screen, Chiappe worked closely with Herron, who remains actively involved in the process. While the show stays largely faithful to the source material, some departures have been made for practical reasons, such as actor availability. Herron reportedly provides feedback and occasionally objects to proposed changes, but generally collaborates constructively.

Chiappe urged caution when writing the scripts, aware that different aspects of the show attract different audience segments—some are drawn to the thriller plots, others to the humor. She also noted input from the actors as an important element in preserving character authenticity, with performers regularly suggesting dialogue adjustments or improvising to maintain their roles’ distinct voices.

Despite its broad international reach, Slow Horses retains a distinctly British sensibility, particularly in its portrayal of flawed, often hapless protagonists. Chiappe observed that the show's depiction of failure intertwined with occasional success resonates uniquely with British cultural attitudes, contrasting with the often more triumph-focused narratives of American television. “There’s something very British in wallowing in failure,” she said.

The sixth series premiered in September, marking a significant milestone in the show’s ongoing run. Chiappe likened the experience of taking over Slow Horses to having “the whole nation marking your homework,” reflecting the high stakes and passionate fanbase invested in the series’ continued quality and tone.