‘Slow Horses’ Season 6: Premiere Date, ‘Joe Country’ And ‘Slough House’ Book Info, And More

It’s become a beloved tradition for Slow Horses fans to devour a new season of Apple TV‘s hit espionage series, then immediately get excited for the next upcoming season. You see, Slow Horses doesn’t just get early renewals. The series kicks off production so swiftly, that when one season ends, a teaser for the next season premieres! And we’re pleased to report that tradition continued after Slow Horses‘ Season 5’s finale.

Based on London Rules, the fifth book in Mick Herron’s Slough House series, Slow Horses Season 5 saw tech master Roddy Ho (Christopher Chung) get a suspiciously gorgeous girlfriend who used him to infiltrate MI5 so she and her team could carry out terror attacks across London. After an eventful finale saw the Slow Horses use their unique skillset to bring down the bad guys, the series gave viewers an exciting look ahead at what to expect from Season 6.

Curious if there will be a Slow Horses Season 6? When will the Apple TV series return with new episodes? And which Mick Herron novels will be adapted this time around? Here’s everything to know about the future of Slow Horses, including Season 6 premiere date info, book summaries, and what we learned from the teaser at the end of Season 5’s finale.

Will There Be A Slow Horses Season 6 On Apple TV?

You bet! Less than a week after its Season 4 finale, Apple TV renewed Slow Horses for Season 6.

Slow Horses Season 6 Premiere Date: When Does Slow Horses Return With New Episodes On Apple TV+?

While an official Slow Horses Season 6 premiere date has yet to be revealed, fans can assume the one season per year tradition will continue. Based on recent seasons, we’ll likely get new episodes in fall or winter 2026, if not sooner. Here’s when past seasons premiere for a refresher:

• Season 1: April 1, 2022 – April 29, 2022
• Season 2: December 2, 2022 – December 30, 2022
• Season 3: November 29, 2023 – December 27, 2023
• Season 4: September 4, 2024 – October 9, 2024
• Season 5: September 24, 2025 – October 29, 2025

How Many Episodes Will Be In Slow Horses Season 6?

Like Slow Horses seasons past, Season 6 will likely consist of six episodes.

What Will Slow Horses Season 6 Be About? And Which Mick Herron Book Does Slow Horses Season 6 Adapt?

Per Deadline, “In Season 6, the spies head out on the run as Diana Taverner embroils them all in a fatally high-stakes game of retaliation and revenge. The sixth season will be based on two of Mick Herron’s novels, Joe Country and Slough House, which are the sixth and seventh in the book series.”

Based on the preview at the end of Season 5’s finale, we have some additional intel on the season ahead, as well. ICYMI, the teaser kicks off with Ho and Lamb knocking at Emma Flyte’s door. At first, she screams, “Will you just fuck off?” But when she see the Slow Horses standing in front of her with a young boy, her curiosity (and ours!) is piqued.

“His dad stole a file with the Slow Horses’ names in it. Now he’s dead and my Joes are being hunted,” Lamb explains. Cut to Molly, who’s working at the Park again, telling Taverner, “Slough House is completely missing.” And in case you needed that phrased another way, another scene shows Ho telling Shirley, “We don’t exist anymore.” Chills.

In true Slow Horses fashion, the stakes are raised and the action unfolds, with the teaser giving glimpses of new characters, guns, fights, car chases, explosions, and more chaos. Lamb meets Taverner outside at night and says, “You got a leak Julian Assange would be proud of.” The next time we see her, a mystery man is grabbing her hands, telling a group of people, “Our security’s in these hands.” The next time we see him, he’s setting a suspicious looking fire. So HMMM… The teaser also shows Lamb, Standish, and Taverner attending a funeral and Lamb warning, “We’re running out of time… It’s a bloodbath.” Oh, and did we mention River and his dear old dad Frank Harkness (Hugo Weaving) come face to face again? Why? “Business.” CHILLS!

Before the teaser ends, Slow Horses lightens the mood by showcasing some of its signature humor. Lamb declares, “We need to address the five Fs. Who the fuck, what the fuck, where the fuck, and why the fuck?” When Coe says, “That’s four,” Lamb snaps, “Fuck off! That’s five!” And we’re left longing for more!

Joe Country Book Plot: What Is The Book 6 In Mick Herron’s Slough House Series About?

Want more info on Slow Horses Season 6? Here’s the synopsis of Joe Country, straight from Herron’s website:

In Slough House, the London outpost for disgraced MI5 spies, memories are stirring, all of them bad. Catherine Standish is buying booze again, Louisa Guy is raking over the ashes of lost love, and new recruit Lech Wicinski, whose sins make him an outcast even among the slow horses, is determined to discover who destroyed his career, even if he tears his life apart in the process.
 

Meanwhile, in Regent’s Park, Diana Taverner’s tenure as First Desk is running into difficulties. If she’s going to make the Service fit for purpose, she might have to make deals with a familiar old devil.

Slough House Book Plot: What Is The Book 7 In Mick Herron’s Slough House Series About?

And since Season 6 is reportedly based on Book 6 and Book 7, here’s the synopsis of Slough House, straight from Herron’s website:

At Slough House, Brexit has taken a toll. The slow horses have been pushed further into the cold, Slough House has been erased from official records, and its members are dying in unusual circumstances, at an unusual clip. No wonder Jackson Lamb’s crew is feeling paranoid. But are they actually targets?  

With a new populist movement taking hold of London’s streets and the old order ensuring that everything’s for sale to the highest bidder, the world’s a dangerous place for those deemed surplus. Jackson Lamb and the slow horses are in a fight for their lives as they navigate dizzying layers of lies, power, and death.

How Many Books Are in Mick Heron’s Slow Horses Book Series?

Heron has written standalone novels, short story collections, and several novellas throughout his career, but there are currently nine full novels in his “Slough House” series, listed in order of publication here:

• Book 1: Slow Horses (2010)
• Book 2: Dead Lions (2013)
• Book 3: Real Tigers (2016)
• Book 4: Spook Street (2017)
• Book 5: London Rules (2018)
• Book 6: Joe Country (2019)
• Book 7: Slough House (2021)
• Book 8: Bad Actors (2022)
• Book 9: Clown Town (2025)

Will There Be A Slow Horses Season 7?

YES AGAIn! On July 8, 2025, months ahead of its Season 5 premiere, Apple TV also renewed Slow Horses for Season 7, revealing in a press release, “In Season 7, Lamb and his Slow Horses are on the hunt to find and neutralize a mole at the heart of British Government before they can bring down the state.” The series is officially Apple TV’s longest-tenured series, so fingers crossed we make it through the rest of Herron’s books.

Stay tuned for more updates on Slow Horses Season 6 (and beyond).