Your Slow Horses series 5 FAQ: Is River Cartwright okay and 5 more questions about the spy drama answered

*Warning: Contains Slow Horses series 5 spoilers

Happy Slow Horses day! Today (Wednesday 24th September) marks the long-awaited release of the fifth series of Apple TV+’s fantastic spy series – and we’re thrilled to be reuniting with Jackson Lamb (Gary Oldman), River Cartwright (Jack Lowden), Catherine Standish and the rest of the gang at the ever-shabby and eventful Slough House. We’re also pleased to announce that it’s as gripping and hilarious as ever – with some shocking plot twists, too.

When you've finished watching the first episode – which is released today on the streamer, with the following episodes dropping weekly – you may well have some questions, from what’s going on with River to whether any of the various figures in the drama are based on real-life politicians. And we're here to answer them...

What’s wrong with River Cartwright?

Our Slow Horses hero, River Cartwright, seems a little off in this series. In fact, he seems strangely distracted, weary and prone to making mistakes – at the beginning, anyway. But we later find out this is due to personal reasons weighing heavily on him. The eminent David Cartwright, River’s retired agent grandfather and the only remaining member of his family that he’s on good terms with, has gone into a home and is deteriorating mentally.

Then there’s the fact that River recently found out that his estranged father, Frank Harkness, is a cruel ex-CIA agent who attempted to recruit him as a mercenary. Not to mention River’s failing relationship with fellow (now ex-)Slow Horse, Louisa Guy (Rosalind Eleazar). Despite River’s attempt to throw her a leaving do, complete with a knock-off Colin the Caterpillar and sad bowls of crisps, she says she needs to take a break - from both him and the service. It’s fair that he’s not feeling his best, then!

What is the shooter’s motive?

In the first episode, we see a mass shooting unfold in a public square. Before this takes place, we see the gunman eating breakfast in a flat with a poster on the wall showing a man holding a woman on a leash like a dog, with the words “body”, “temple”, “woman” and “dog” - suggesting there could be a misogynistic motive. Later on in the series, we’ll see this take another twist - as other events are connected to Libyan terrorists who want revenge for Britain’s mishandling of the political vacuum in their country.

What is a honeytrap plot?

Episode one finds Slough House hacker Roddy Ho - an insufferable tech genius - get a girlfriend. This raises immediate suspicions among his colleagues, who are shocked that he’d find a woman willing to go out with him. River, Shirley and Catherine tail him as he meets up with Tara, following the pair to a nightclub. Although Roddy is unwilling to admit it, Tara is in fact a honey trapper, playing on his emotions to gain access to the inner workings of MI5.

Honeytraps are plots used by spies to glean national secrets - an individual uses romantic or sexual techniques to manipulate another person into revealing confidential information. The targeted individual may be courted for a relationship, or a fling, sometimes using emotional manipulation.

When was Mick Herron’s London Rules written?

Slow Horses author Mick Herron wrote the book in 2018 - but the release of the series in 2025 feels strangely timely with rise of a populist politician and protests over climate change. When GH asked Mick about the political angle to the book, he said that “Brexit was certainly the trigger for London Rules. And, kind of retrospectively, it affects the earlier books in a strange sort of way. That’s when the readership started to take off.”

Are any of Slow Horses series 5’s characters based on real people?

As we mentioned, series 5 has a timely feel in terms of politics, and some viewers have drawn comparisons between populist leader Dennis Gimbal and Nigel Farage. Then there’s Zafar Jaffrey, who’s running to be the Mayor of London in the series, who’s been compared to real-life Mayor Sadiq Khan. Speaking at a screening of the series recently, Ted Lasso actor Nick Mohammed, who plays Jaffrey, addressed this, saying: “I think that there will inevitably be people who are drawing comparisons to the current Mayor of London, but [...] this was written a while ago. Yes, I guess it is quite sad that some of it feels really current now, but he's not based on one particular person.”

He continued: “I think [Jaffrey] represents a side of politics, which I guess is left-leaning, but he's by no means without fault. He's vain, he grandstands a lot, he likes the sound of his own voice, he uses as many things as he can to his own advantage. He tries to score political points. So he's dynamic in that way and he's quite complicated. He’s sort of an amalgam of lots of different politicians, really.”

When we asked Mick Herron about character Peter Judd - the former Conservative Home Secretary - and his resemblance to Boris Johnson, Herron replied, laughing: “Anyway, we needn’t go into that!”

Slow Horses series 5 premieres today, Wednesday 24th September, on Apple TV+, followed by one episode weekly until 22nd October. You can also stream series 1-4 on Apple TV+ now.