Apple TV's 'Slow Horses' Is Officially Facing a 'Game of Thrones'-Sized Problem With Season 8

Published Sep 25, 2026, 6:31 AM EDT

Erin Konrad's love for everything entertainment dates back to elementary school when she became obsessed with classic Hollywood musicals. When she's not catching up on all her favorite television shows, she's advising her friends and family on what they should binge watch next.

She has her Bachelor's degree in Journalism and a Masters of Fine Arts in Creative Writing. Creating content for Collider gives her the opportunity to combine her writing skills with her passion for television and movies. She spends her free time trying to beat her personal record of reading 137 books in a year and cuddling with her dog, Gracie.

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Apple TV's Slow Horses is currently one of the best shows on television. With a wildly impressive 98% Rotten Tomatoes score and a growing number of Emmy nominations, it's clear that the spy thriller is winning over people left and right. Season 6 just premiered this month and is already delivering plenty of shocking twists. With the series already having been picked up for Season 7, it was recently announced that an eighth season has been greenlit as well. However, even though Slow Horses' long-term renewal is good news, it does raise a significant issue that will need to be addressed.

Apple TV's 'Slow Horses' Has Faithfully Adapted the Books So Far

Apple TV's Slow Horses is adapted from the bestselling book series by Mick Herron. The first season, which aired in 2022, is based on the first book in the Slough House series, which was published in 2010. Every subsequent season has been adapted from one of Herron's novels, of which there are nine main books as well as a few novellas and short stories.

At first glance, it seems like there'd be more than enough source material to keep the show going for a long time, except that Season 6 has combined two novels, Joe Country and Slough House, for its plot. With the confirmation that Season 7 will adapt Herron's eighth book, Bad Actors, and that Slow Horses has been renewed for an eighth season — presumably set to tackle Clown Town — it raises a bigger question: will Slow Horses continue past Herron's published books?

'Slow Horses' Is Potentially Facing a Major Problem Beyond Season 8

Slow Horses has already experienced a significant change in direction with the exit of its original showrunner, Will Smith, after Season 5. With Gaby Chiappe taking over the reins for Season 6, while Ben Vanstone is slated to take the helm for Season 7, the show faces even more uncertainty once it catches up to Herron's last published Slow Horses novel. If Apple TV's adaptation continues, it would need to chart its own path forward with completely original storylines. The Slow Horses writers are an incredibly talented bunch who are probably more than capable of continuing the stories of Jackson Lamb (Gary Oldman) and River Cartwright (Jack Lowden) without a book to draw from. Many other shows have expanded past the source material in ways that allow the storytelling to flourish; The Handmaid's Tale, The 100, The Leftovers, and Watchmen all became unique entities by diverging from the stories they were based on.

There's also the possibility that the Slow Horses team would decide to put a pause on future seasons until Herron can publish another book. This would be unfortunate, since the show has maintained a reliable release strategy every single year, besting so many other streaming shows out there. There is one more option for the series, but it's one that fans of the show won't like to hear. Slow Horses could very well conclude with its eighth season. If the writers stick to following Herron's series, it could make sense for the series to conclude in a way that wraps up everything in a neat bow.

It'll be interesting to see how Slow Horses continues, whether that means embracing a completely original story or bringing the series to a more definitive close. No matter what path the team decides to pursue, we'll be devastated once this spy thriller does come to an end.

Slow Horses Season 6 is available to stream on Apple TV in the U.S. New episodes drop every Wednesday.

Slow Horses