Slow Horses actor reveals the character author Mick Herron said is most like him

Speaking exclusively to Radio Times ahead of the premiere, Brooke – who plays JK Coe in the show – said of meeting Herron: “I met him on my last day. It was going to be before then, but it never happened. Mick told me that Coe is the character who’s most like him.”

Slow Horses fans will remember JK Coe from season 4, when he was introduced as a mysterious figure who didn't speak much (or at all, really).

Opening up about his character, Brooke previously told RadioTimes.com and other press: "His name is Jason Kevin Coe, he's embarrassed by both his first names and so he goes by JK.

"His overall vibe is he just wants people to leave him alone. He's got PTSD, which he keeps in check by pretending to play the piano."

He added: "But Mick Herron has written him into two books. There's a novella called The List, but there's another really good full-length called Nobody Walks, which is sort of a Slough House universe book, which basically gives you his backstory, and it is absolutely horrific.

"So I just did that, really. I've never had a backstory given to me in that way. But if it's there and it's that good, best not to mess with it, really."

The synopsis for season 5 teases that "everyone is suspicious when resident tech nerd Roddy Ho has a glamorous new girlfriend, but when a series of increasingly bizarre events occur across the city, it falls to the Slow Horses to work out how everything is connected".

It continues: "After all, Lamb knows that in the world of espionage, the London Rules – cover your back – always apply."

We know that there’ll be at least two more seasons of the show, with seasons 6 and 7 already confirmed.

However, there’ll be a big change behind the camera for those upcoming seasons, with the fifth instalment of the show marking the last time showrunner Will Smith will be at the helm.

The new issue of Radio Times is on sale from Tuesday 16th September 2025.

Slow Horses season 5 releases on 25th September 2025 on Apple TV+ – sign up to Apple TV+ now.

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