While the season has blended elements from both books 6 and 7, Joe Country and Slough House, this does mean that certain plot elements from the novels have been ditched, with cuts particularly affecting the former's story.
Now, while speaking exclusively with Radio Times, Roddy Ho star Christopher Chung has revealed the element of the novels he is most sad not to have gotten to portray on screen – and, perhaps naturally, it involves travel.
"I think the thing that we were all anticipating was going to Wales in the snow," Chung said, "and there was a moment where it was floated that we might go to a Scandinavian country to film in a snow covered field somewhere.
"We were all kind of psyched to go on a Slow Horses field trip that didn't happen."
Chung is referring to a central element of the plot of Joe Country, which sees the Slow Horses travelling to rural Wales in the dead of winter.
Director Adam Randall previously explained why the two books were merged for the season, saying that: "Joe Country would make the most amazing film, but it was felt that there was not a huge amount of story for a number of our characters."
He explained: "Taverner’s not in it a great deal, Lamb hasn't got a huge amount to do, so it was sort of the decision to combine [Joe Country and Slough House] and find a way for them to work together.
"But then we had the opportunity to draw on both of them throughout the process, which was really fortunate."
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Slow Horses has already been renewed for two more seasons on top of the current one, meaning the show will adapt novels 8 and 9, Bad Actors and Clown Town.
It is currently uncertain what will happen beyond that, as the show will have then adapted all of the books Herron has currently written in the mainline series.
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