Warning: This article contains major spoilers from “Slow Horses” Season 6, Episode 6.
“Slow Horses” Season 6 is over, and things may very well never be the same again.
The Apple TV series’ Season 6 finale, aptly titled “Judgment Day,” bring things to a brutal, bloody and shocking conclusion. Much of the episode follows River Cartwright (Jack Lowden) and the rest of his Slough House survivors as they fight for their lives against Frank Harkness (Hugo Weaving), his hired mercenaries and vengeful Russian assassin Jane (MyAnna Buring), who gets taken out in nonchalant fashion by Weaving’s Frank as she is on the verge of killing River.
The Slow Horses succeed in protecting endangered witness Reece (Lenny Rush), but not without suffering yet another heartbreaking casualty when Frank mercilessly guns down Emma Flyte (Ruth Bradley) in broad daylight after she manages to take out one of his hired goons. Jackson Lamb (Gary Oldman), meanwhile, convinces right-wing media mogul Damien Cantor (Harry Lloyd) to call off Frank, before handing him over to the Russians in a save-our-own-butts pact made between Lamb, a scrambling Diana Taverner (Kristin Scott Thomas) and Cantor’s Russian handler, Natasha (Zrinka Cvitešić).
River lets Frank go and he and the remaining Slow Horses gather with Lamb in the episode’s closing minutes to honor this season’s fallen — namely, Flyte and J.K. Coe (Tom Brooke). River later realizes that Sid (Olivia Cooke) got away from her MI5 pursuers and is waiting for him at his grandfather’s countryside home. For a moment, it looks like “Slow Horses” Season 6 is going to end on an uncharacteristically optimistic, romantic note.
And then River decides to surprise Sid. Hearing her upstairs, he begins putting together dinner for her. While doing so, he moves the crowbar that he brought into the house all the way back in the second’s second episode, and which Kyle Soller’s Jim ominously eyed in “Slow Horses” Season 6, Episode 3. A moment after he touches the crowbar, River’s hand begins to sting and shake. It is only seconds later that his whole body is convulsing, on the receiving end of an attack by the Russian nerve agent planted on the crowbar by Jim.
In a moment ripped straight from the pages of author Mick Herron’s 2021 novel, “Slough House,” “Slow Horses” Season 6 ends on an image of River’s body convulsing on the floor, right next to the dinner date that he and Sid may never get to share. According to Season 6 head writer Gaby Chiappe, the plan was always to follow Herron’s lead in “Judgment Day.”
“It is the most extraordinary cliffhanger. It reminded me of reading ‘Game of Thrones’ and thinking, ‘Wait, what? Ned Stark’s dead?!?’” Chiappe told TheWrap. “I was just so on the edge of my seat for the next novel to come out so I could find out what happened. It’s a proper cliffhanger. You don’t know where it’s going.”
“It’s a really interesting thing Mick did,” Chiappe added. “It’s a bit, like, ‘You know I’ll kill people. But you think I’ll kill everyone except Lamb and River. Well, what if I do this to River?’ You don’t know if he’s dead or alive. It felt like a real upping of the stakes in a way that was really exciting to do, especially when something is beloved and running smoothly, which the novels are and the show is as well.”
Chiappe declined to confirm whether River is dead at the end of “Slow Horses” Season 6. Cooke similarly could not speak on her “Slow Horses” future when TheWrap spoke with her. However, when asked if she would be interested in returning again, Cooke was quick in her response.
“Oh yeah. I really adore everyone. The set is just glorious to be a part of. We just all laugh a lot,” Cooke said. “When we filmed this season, there was a moment with [Season 6 director] Adam [Randall] where [the characters] were getting chased and I was in a car, and I just had this huge smile on my face. He was like, “Olivia! Don’t smile! This is bad!” I was like, “Oh, s—t!” [Laughs] It was just unbridled enjoyment.”
In hindsight, River and Sid’s poisoned dinner date is a fitting way to end what proved to be the most violent “Slow Horses” season to date. Multiple prominent characters met their ends this season, and that is not to mention the high number of new and periphery “Slow Horses” figures who were also taken off the board over the course of these last six episodes. It is a wonder — and a testament to the Apple TV series’ unwavering tonal magic — that it managed to do all of that this year and deliver the show’s first true romance with River and Sid.
Cooke, for her part, was delighted to bring a “really delightful new texture” to the spy thriller this season. “It did feel like, as we were working on the arc of their relationship, that it was building up to this crescendo moment when they’re at the airfield [in Episode 5] and they kiss,” Cooke said of River and Sid’s slow-burn romance. “That wasn’t scripted. We felt like we needed to put that in there because we thought, ‘Oh, these two characters deserve it and also the audience deserves this as well.’ It felt like a John Hughes moment, really.”
“They’re not skilled when it comes to romance. Sid, I think, has lived a very lonely existence the last four years. I don’t think she’s had any action for a while. River, we’ve seen him try and fail. They’re not Cassanovian!” Cooke observed with a laugh. “They’re very awkward when it comes to putting their heart on their sleeve, and that feels scarier to them than the missions that they go on.”
It was, in fact, River and Sid’s unlikely romance that made Chiappe so excited to get to handle the show’s adaptation of “Slough House.”
“It’s my favorite novel because I love that River and Sid get together in it. It was amazing to be able to be involved in that, in bringing that character back and writing for Olivia Cooke, who’s so brilliant,” Chiappe explained. “She gets such a small amount of screen time in Season 1, and you so remember her. She’s so delightful and so funny and so ‘Slow Horses.’ Bringing her back was just brilliant.”
Viewers only catch a brief glimpse of Sid in the “Slow Horses” Season 6 finale. Cooke nonetheless offered some insight into what she thinks is going through her character’s mind while River puts together his doomed, spur-of-the-moment romantic dinner.
“Thinking longterm is maybe the downfall of a spy. So I think she’s just focused on putting one foot in front of the other,” Cooke mused. “She’s like, ‘I’m gonna get to this house. I’m gonna shower all this s—t off me. Put a comb through my hair. Put some dinner on the table with a bottle of wine and let’s just sit down and have a date. Let’s just strip it all back and have a chat.” [Pause] She’s probably wanting to get laid, too. She’s probably horny. All that adrenaline… it’s potent. [Laughs]”
It is ultimately a cruel bit of injustice that River’s fate is left unknown in the same “Slow Horses” episode where he chooses to let his murderous, mercenary father live. Frank has now killed — or been responsible for — more Slough House deaths than any of the show’s other villains. While many of the series’ survivors seem primarily focused on just surviving at this point, though, there is one person who may still be interested in actually getting some revenge on Frank.
Jackson Lamb himself.
The two veteran spies briefly collide around the midpoint of “Slow Horses” Season 6. It was with that in mind, Frank and Lamb’s Shake Shack confrontation, that TheWrap asked Oldman before the season premiered whether he believes Lamb would prefer to finally take down Weaving’s hitman-for-hire. The actor paused for a moment before answering.
“I think he would probably like to take him off the board,” he said. “We don’t really know quite what Lamb is capable of. We have the [Charles Partner scene] in Season 1. We get these little tastes of what Lamb possibly could have been like back in the day. He even says, I think, to River in Season 1, ‘If you don’t want to be around death, then you should just get out the car right now. You’re going to see a lot more of it.’”
“I think with someone like [Frank], Lamb would rather just completely take him off the board,” Oldman concluded. “Slow Horses” fans are likely in agreement with him about that.
“Slow Horses” Season 6 is streaming now on Apple TV.
