Slow Horses doesn't mess around. Fans don't have to stress about whether Apple TV is going to have the spy thriller return because the streamer makes renewal decisions early. Not only do we already know that Slow Horses will return for season 7, but season 8, too.
What Slow Horses season 7 looks like isn't extremely clear at the moment. We know the season will be based on one of Mick Herron's Slough House novels, of course, but some characters definitely won't be coming back, and whether a key character will return is unknown. That would be River Cartwright, played by Jack Lowden.
There are some small spoilers ahead for some of Herron's books!
River doesn't actually die in the Slow Horses books
The latter is important. At the end of season 6, Cartwright is poisoned after picking up a bottle of wine. Now, everyone wants to know if River is dead. Thankfully, we know that, in Herron's book series, Cartwright survives.
The problem is that in real life, Lowden has been linked to the role of James Bond, which could impact his availability for season 7. Lowden hasn't officially been named to that role, but if he is, he likely won't be returning as Cartwright.
The positive is that because Slow Horses begins production on a new season before the last one ends, Lowden, even if he does get the role of Bond, likely, was available for season 7. The negative is that we don't see him in the season 7 teaser after the finale of season 6. That would make sense, though, because otherwise the series creators would have just diminished the ending of season 6.
Besides the Cartwright issue, we do know a lot about the next season, and can even guess pretty closely at when season 7 will begin.
Slow Horses season 7 will be based on Herron's novel, Bad Actors
Apple TV has already let us know that, too. According to a press release from the streamer, the season will be based on Herron's novel, Bad Actors, part of his Slough House series (of which there are nine novels). Jackson Lamb (Sir Gary Oldman) and his agents have to try to find a mole buried in the British government before the mole brings down the entire UK.
Based on the teaser at the end of season 6, the storylines from the latest season will somewhat roll over to the new one. GRU head Vassily Rasnikov has arrived on British soil with unknown intentions. We know this because First Desk Diana Taverner (Kristin Scott Thomas) says so.
Lamb is also asked by his assistant, Catherine Standish (Saskia Reeves), where he has heard from Cartwright, and Lamb responds, "Yeah, funny enough, I got a postcard. ‘Weather’s lovely in the afterlife. Sunsets to die for. Love and hugs.'"
So, we still can't be sure Cartwright returns, but he's at least mentioned.
Slow Horses season 7 already wrapped filming
Production on Slow Horses season 7 wrapped in early 2026. While we already know the season has been filmed, no official date has been announced. Based on when previous seasons have started, a fall 2027 date is almost certain.
Season 6 began on Sept. 16, 2026, and season 5 began on Sept. 24, 2025. In fact, the last five seasons have begun in the fall, with the last three in September. With filming officially wrapped on season 7, there's no reason for Apple TV to hold it beyond the fall of next year.
The other safe assumption is that Slow Horses will return in 2027 because the series has been an annual event since 2022. There would be no obvious reason why that would change next year.
We should also assume that season 7 will consist of six episodes. Every season so far has had that many.
Gary Oldman is back as Jackson Lamb in season 7, along with key cast members
There are a lot of characters and cast members already confirmed for Slow Horses season 7, including Gary Oldman as Jackson Lamb, Kristin Scott Thomas as Diana Taverner, and Saskia Reeves as Catherine Standish.
What about Lowden as River? This is a tricky part, of course. We don't see River in the teaser trailer, but he is still a character in the books, as he survives the poisoning that occurred in season 6. We don't know if he survives in the streaming series.
Unfortunately, since season 7 will happen in the future, we can assume those characters lost in season 6 won't return as main roles, at least. The list is long and includes Emma Flyte (Ruth Bradley), JK Coe (Tom Brooke), and David Cartwright (Jonathan Pryce), all of whom died in season 6.
We'll share more updates about Slow Horses season 7 when we find out! That's all we know for now!
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