Books, Cast, Premiere Date, Trailer, More Details

Slow Horses returns for its fifth season this fall, to continue telling the Apple TV+ adaptation of Mick Herron’s Slough House book series. But what about its future beyond that?

The drama starring Gary Oldman has gotten early renewals from the start, with, for example, the Season 5 pickup coming just days after the Season 3 finale began streaming. With Season 5 premiering on September 24 (with one episode), below, we’re taking a look at everything we know so far about Slow Horses Season 6, including the book on which it will be based, a premiere date, and more.

Is Slow Horses renewed for Season 6?

Yes! Apple TV+ announced that Slow Horses will be back for a sixth season in October 2024, less than a week after the fourth season’s finale began streaming. It will consist of six episodes.

“Audiences around the world have fallen in love with the Slow Horses, and I’m delighted that Gary Oldman will be leading this star-studded cast on another acerbic and action-packed adventure,” said Jay Hunt, creative director, Europe, Apple TV+, in a statement at the time.

When will Slow Horses Season 6 premiere?

It’s too soon to tell. Season 1 was released in April 2022, Season 2 in December 2022, Season 3 in November and December 2023, Season 4 in September and October 2024, and now Season 5 is set for September and October 2025. Season 6 has already been filmed, so it should be released sometime in 2026, likely in the fall.

On which book is Slow Horses Season 6 based?

Season 6 will actually cover two books, the sixth and seventh in Mick Herron’s series, Joe Country and Slough House.

The Joe Country synopsis reads as follows: “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… And with winter taking its grip, Jackson Lamb would sooner be left brooding in peace, but even he can’t ignore the dried blood on his carpets. So when the man responsible for killing a slow horse breaks cover at last, Lamb sends the slow horses out to even the score.”

And the Slough House synopsis is: “At Slough House — MI5’s London depository for demoted spies — 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.”

What is Slow Horses Season 6 about?

According to Apple TV+, it “sees the Slow Horses on the run as Diana Taverner embroils them all in a fatally high-stakes game of retaliation and revenge.”

Who’s in the Slow Horses Season 6 cast?

We’ll have to wait to see how the fifth season plays out to see who returns. The Season 5 cast consists of Gary Oldman (Jackson Lamb), Kristin Scott Thomas (Diana Taverner), Jack Lowden (River Cartwright), Saskia Reeves (Catherine Standish), Rosalind Eleazar (Louisa Guy), Christopher Chung as (Roddy Ho), Aimee-Ffion Edwards (Shirley Dander), Ruth Bradley (Emma Flyte), James Callis (Claude Whelan), Tom Brooke (J.K. Coe), and Jonathan Pryce (David Cartwright).

Is there a Slow Horses Season 6 trailer?

No, one won’t be released until after all of Season 5 if streaming.