Slow Horses is back on 16 September and done by 21 October — six episodes to answer what last year's finale left hanging

Summer on Apple TV has just wrapped – we had feel-good comedies like Ted Lasso, a hefty lore dump for Silo, the lot. But really, the Big One for the autumn telly schedule is Slow Horses, which is back for its sixth outing. For those not up to speed: it’s the sharp, darkly funny MI5 series about the reject agents shunted into ‘Slough House’ and led, gloriously, by Gary Oldman as Jackson Lamb. Every new series announcement feels less like a streaming drop and more like an event. On to what’s actually changing this year, when you’ll get it, and why season 6 is a little different to the rest.

Slow Horses season 6 starts on 16 September 2026 and runs weekly through to 21 October.

How It's Dropping

Apple isn’t doing the binge-drop for Slow Horses this time either – just as with previous seasons, they’re sticking to weekly releases. Six episodes in total, all spaced out across the autumn. If you’re marking calendars, the line-up looks like this:

• Episode 1: "Circle of Life" – 16 September
• Episode 2: "Daddy Issues" – 23 September
• Episode 3: "Resurrection" – 30 September
• Episode 4: "Lost and Found" – 7 October
• Episode 5: "Sayonara" – 14 October
• Episode 6: "Judgment Day" – 21 October

If you’re tracking the release history, it’s been brisk: season 1 landed in April 2022, then season 2 that December, which was a nice Christmas bonus, frankly. Since then it’s gone almost yearly – November 2023 for season 3, September 2024 for season 4, and September 2025 for season 5. No endless gaps or streaming wilderness. Especially handy, given last year’s finale dug into Lamb’s backstory and delivered a wicked cliffhanger – no one wanted to be left dangling for ages waiting on answers.

New Ingredients for Season 6

This year, there’s a proper shake-up on two fronts. For the first time, the story for season 6 isn’t pulling from just a single novel but two books by Mick Herron: that’s Joe Country (book 6, published in 2019) and Slough House (book 7, from 2021). So, if you’ve read either, expect to see those threads twisted together. The other big shift is behind the scenes: Will Smith, main writer and producer since day one, has exited, and Gaby Chiappe (previously co-exec) is now in the main seat running the script. Could be an interesting change in tone – or not; sometimes, these swaps are seamless on the viewing side.

The official logline (from Apple, so you can probably guess the marketing spin) is all about the crew getting dragged into a “fatally high-stakes game of retaliation and revenge” thanks to Diana Taverner (Krysten Scott Thomas). In short: the entire lot of them are on the run and in the firing line. Given those episode titles – ‘Judgment Day’, for one – it’s safe to assume the stakes are getting ramped right up before the credits roll on 21 October.

Here’s the official tease as Apple puts it: "the Slow Horses on the run as Diana Taverner (Kristen Scott Thomas) embroils them all in a fatally high-stakes game of retaliation and revenge."

What Next?

Don’t go booking in grief leave after October – star Christopher Chung (who plays Roddy) has dropped a little hint to ScreenRant that season 7 isn’t just a nice idea: "I think that 2027 is a good bet for season 7." So, once the dust has settled from this run, there’s more in the pipeline. If you’re the rewatching type, that’s precisely the gap to start again from the top, no harm done before next year rolls around.