Slow Horses cast talk season 5 and beyond: "It's a very thin tightrope"

Now, three of the show's stars who have been with it since season 1 - Jack Lowden (River Cartwright), Saskia Reeves (Catherine Standish) and Christopher Chung (Roddy Ho) - have weighed in, while speaking at a special BFI screening for the fourth season's first episode, in collaboration with Radio Times.

Asked whether he would like to see more seasons of the show beyond the fifth outing, Lowden, remained coy, saying: "I mean, as a punter, yeah, because it's just a joy to watch."

"So many of our bosses are in the audience tonight," he joked. "Season 5 was, again... it's unbelievable that they seem to manage to find different things and different places to take this lot.

"And also, the unique challenge you have with something like this is that a world has been created through these characters that you don't ever want to go too far away from. You don't want a s**t fifth album or something, where the comfort of why people watch this and why people love it... you don't want to take that away.

"So it's a very thin tightrope for people to walk that are making this. Yeah, season 5 is good fun."

Reeves added: "We also have the opportunity of bringing in new characters, and therefore new actors and different actors. There's lot to look forward to."

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Chung said of the new characters each season: "They all just change the dynamic slightly, and it throws up more questions for each of our characters every time we get to interact with a new cast member.

"And I think that's the thing that's quite exciting about looking forward to whatever in the future, is that you can continue to ask these questions because they're always getting thrown by whoever is coming in."

Lowden, Reeves and Chung aren't the only ones talking about the show's future - showrunner Will Smith has previously teased that the show could run for nine seasons to cover all of Herron's novels, while Tom Brooke, who plays new Slough House addition JK Coe, has said he would be game for a spin-off telling his character's backstory.

Slow Horses season 4 will stream on Apple TV+ from Wednesday 4th September – sign up to Apple TV+ now.

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