Following three critically acclaimed seasons and a steadily growing audience, Slow Horses is returning for season 4 on Apple TV+. The series, which is adapted from novels by Mick Herron, tells the story of a group of MI-5’s worst agents who constantly find themselves in the middle of various international incidents. Thanks to a brilliant central performance from Gary Oldman and a remarkably deep cast, the show has earned a loyal following over the course of its first three seasons.
If you’ve been looking forward to the upcoming fourth season (as well as the fifth that has already been announced), we’ve got a rundown of everything we know about the upcoming season, including details on the plot, casting, and potential release date.
What’s the plot for Slow Horses season 4?
The fourth season will follow the events of Herron’s fourth book, Spook Street, and will involve the agents of Slough House getting sucked into a terror attack on a crowded London street. The season will also follow up on the aftermath of River’s release of the “Footprint” file, which ultimately got Tearney promoted to first chair at MI-5.
There’s also an outstanding question about whether River and Louisa might find themselves romantically involved. Showrunner Will Smith promised Decider that things would be getting a little “messy” on that front:
“Yeah, we’ve definitely played with that, I would say. And I think that comes from their performance, that comes from that hug as much as anything. And I think people would want to see them together, but all I could say is we’re going to be true to the character dynamics of the books. But it’s definitely — the question will not go unanswered. Put it that way. It’ll be in a Slow Horses way. And it will be messy. I can’t give too much away.”
Who is in the cast for Slow Horses season 4?
All the living cast members from previous seasons of the show, including Gary Oldman, Kristen Scott Thomas, Jack Lowden, Jonathan Pryce, Saskia Reeves, Steven Waddington, Rosalind Eleazar, and Paul Higgins are all expected to return. In addition, the new season will also include Hugo Weaving, Tom Brooke, James Callis, Ruth Bradley, and Joanna Scanlan.
When is the release date for Slow Horses season 4?
We don’t have a firm release date for the fourth season yet, but Smith told Decider in December of 2023 that the season would premiere before that time the following year (December 2024). Production happened in the spring of 2023, and has already wrapped up (it was shot immediately after season 3), so it seems safe to say that the fourth season will debut before the end of 2024.
Is there a trailer for Slow Horses season 4?
No trailer has been released for the fourth season yet, but a preview was released at the conclusion of season 3 that offers a tantalizing hint at what’s to come. In addition to previewing the bombing and several new characters, Oldman’s Jackson Lamb also mentions that one of his team has just died. To find out which team member that is, we’ll just have to tune in.
