Slow Horses season 3 spoilers follow.
Slow Horses writer Will Smith has hinted at how the latest finale twist sets up season four.
The Apple TV+ spy thriller wrapped up its most recent season today (December 27) with an episode filled with betrayals and shocking discoveries in Slough House.
Among the bombshells in the episode was Catherine Standish's (Saskia Reeves) discovery about Jackson Lamb's (Gary Oldman) involvement in the demise of the traitorous former director-general of MI5, Charles Partner (Game of Thrones' James Faulkner)
"It's pretty explosive at the end of this season," Smith told Digital Spy. "The only bit of the puzzle that she can put together is the fact that it was Lamb that did it and it's whether she intuitively knows that underneath it or it needs to be spelled out.
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"In the book, she's directly told at one point and we have the knock-on from that. We will probably get to that, yes."
Slough House could also be at the centre of an international incident next season, due to MI5 agent River Cartwright (Fighting With My Family's Jack Lowden) leaking the infamous 'Footprint' document.
"Where it ends in season 3, where Taverner thinks she's got what she wants – let's just say that there's a recalibration of that at the start of the next series. There's repercussions, but they're more left field than directly to do with leaks," Smith teased.
The writer also touched on Slow Horses' mix of dry comedy and intense mystery — and how he's able to balance them both.
"With all of them, I will be biting my finger at points and that's the thing: it manages to be funny but still be plausible," he said. "You're laughing, but you don't feel you're watching a comedy. If we can keep that going then we'll be alright."
Slow Horses is available to stream now on Apple TV+.
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Critic and writer Jo Berry has been writing about TV and movies since she began her career at Time Out aged 18. A regular on BBC Radio, Jo has written for titles including Empire, Maxim, Radio Times, OK!, The Guardian and Grazia, is the author of books including Chick Flicks and The Parents’ Guide to Kids’ Movies.
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