How Many More Seasons of Slow Horses Could There Be?

• Apple TV renewed Slow Horses for an eighth season, making it the longest-running show on the streamer, with season 8 set to adapt Mick Herron’s most recent Slough House entry, Clown Town.
• The future of Slow Horses beyond season 8 is uncertain, as the series may need to make decisions on how to proceed without new source material from Herron, potentially leading to changes in the show’s direction.
• Despite Herron’s confirmation of more books to come, the show’s executive producer hinted at the possibility of more seasons beyond season 8, leaving the ultimate decision in the hands of Apple TV.

Ahead of its season 6 release in September 2026, Apple TV renewed Slow Horses for an eighth season. The renewal made the British spy thriller series the longest-running show on the streamer, and fans seemed pretty happy. Why wouldn’t they be? While other great shows are getting canceled or wrapping up their stories, Slow Horses just keeps on running, and there doesn’t seem to be an end in sight.

Yet season 8 could inspire some big behind-the-scenes decisions for those shepherding the TV version of Mick Herron’s bestselling book series onto the small screen, as it will adapt the events of his most recent Slough House entry, Clown Town. After season 8, the Apple TV series could be up to date with Herron’s beloved tales of hapless espionage, which may mean some changes ahead.

Slow Horses typically releases a season every year, so season 8 could realistically arrive in 2028. Herron isn’t done writing Slough House books, but if he doesn’t release another one (or even two) in good time before then, the series will be faced with a few choices: keep going with the writing team’s own ideas à la Game of Thrones, consult with Herron about any firm or detailed ideas he has for future instalments, delay work on further seasons and wait for the author to create more books, or put an end to the show.

Herron has churned out nine Slough House novels and five novellas since 2010, so we can’t imagine Slow Horses fans will be left dealing with a Winds of Winter-esque situation here, but a lack ofs have had to consider

“Most TV shows don’t have books, so we can figure this out,” executive producer Douglas Urbanski told THR. “And there’s another thing: Mick Herron hasn’t stopped writing. I can’t speak for Mick, but you never know, more books might be coming.” Indeed, Herron confirmed to the Radio Times last year that “There will be more to come. I haven’t decided how many yet but I’m enjoying myself and don’t plan to stop just yet.”

Yet until any new books are released, season 8’s spin on Clown Town could mark the end of one particular creative road for those adapting Herron’s work. As many fans already know, the story features Jackson Lamb and Diana Taverner’s ageing spies (played by Gary Oldman and Kristin Scott Thomas, respectively) as they’re forced into a dramatic face-off after someone tries to blackmail the Park.

Oldman recently revealed at the Edinburgh TV Festival that it’s a “struggle and a fight” to keep the cast together and “keep on top of the quality” of Slow Horses, but he also told TV Insider that Apple TV will ultimately decide whether to “keep it going or end it.”

With Season 8’s renewal confirmed, it seems fans will have another two seasons of Slow Horses to look forward to after the current one wraps up. Beyond that, the show’s future is currently unclear.