Slow Horses season 2 differs from the book in a major way

While the first season was largely faithful to the source material, there were some deviations as it rattled towards the end, one being the expansion on Lamb's involvement in the death of Charles Partner, colleague of fellow Slough House exile Catherine Standish.

There were also hints that Olivia Cooke's Sid Baker may not have met her demise earlier in the series, which is alluded to much further down the line in the novels.

Season 2, based on the second book in the collection Dead Lions, has also strayed from Herron's plotting in places, with the major divergences listed below.

From Upshott with Love

Season 2 follows the basic outline of the book but begins to deviate early on, with River Cartwright's undercover operation in the sleepy village of Upshott, where Dickie’s killer was last spotted, travelling in a different direction. River scopes out the village for clues about Dickie’s murder in both the series and the novel, but the manner in which the investigation unfolds varies drastically.

In the series, the only locals we cross paths with are Kelly Tropper's parents Duncan (who owns the flying club) and Alex.

In Dead Lions (the second novel), the investigation into events in Upshott is far grander in scope, with River encountering many of the locals in the pub and through his digging, whereas in the series it feels more intimate just focused on the Troppers, although this may have been in part due to COVID restrictions at the time of filming. The novel has a grander conspiracy at play including an MOD site and a larger portion of the village ultimately revealing themselves to be Cicadas.

With much of the book focused on River’s storyline and the series spinning many plates, it makes sense for the show to streamline the story somewhat, expanding the role of some of the other Slough House members.

Min's demise

As in Dead Lions, Min Harper makes a surprisingly early exit after proving himself to be an integral part of the team in the first season. This forms a key part of the storyline in both, with heavy implications for Louisa Guy and the Slough House team more broadly.

Min is drugged by the Russians that he's monitoring alongside Louisa but unlike the book, which is somewhat ambiguous, we see Min's death and the events leading up to the discovery of his body laid out in much more detail on screen, further emphasising Louisa's need for vengeance.

Shirley & Roddy

Shirley Dander is a new addition to the Slough House crew in season 2. Unlike the novels, which give her more to do further down the line, she has a meatier role in the adaptation.

We see Shirley trying to help retrieve CCTV footage for the investigation into Dickie’s death, and she's involved in a thrilling chase on a train with Roddy, which wasn't the case at this stage in the novel. That decision ups the stakes for both characters and helps the audience to form more of a connection to Shirley.

The team behind the show also ditched Shirley's cocaine habit, which is a key part of her character in the books.

Lamb and Cartwright

Beyond some of the changes to the plot of Dead Lions, some of the storylines alluded to in the first season are expanded upon, with Lamb doubling down on his involvement in the death of Charles Partner, something hinted at throughout the books but not directly addressed until much later.

David Cartwright's role is also expanded, with the retired MI5 officer given a crucial role in the conflict's culmination. Surprisingly, light isn't shed on Sid Baker's whereabouts, but if the novels are anything to go, there's plenty more to come from that strand of the story.

While still faithful to the core of Dead Lions, Slow Horses season 2 does expand on some of the book's details to give some of the characters meatier roles and to build on some of the work laid out in the first season. Far from proving detrimental, the majority of the changes make sense, helping to keep the narrative flowing and in some cases, increase the stakes.

With seasons 3 and 4 on the way, there's plenty more where that came from.

Episodes 1-3 of Slow Horses season 2 are available to watch now on Apple TV+, with further episodes airing weekly. Sign up to Apple TV+ now.

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