*WARNING: Contains major spoilers for all six episodes of Slow Horses season 6.*
The sixth season of Slow Horses has come to a dramatic end.
It’s been a particularly dark season, with several major characters meeting grisly ends, including David Cartwright and former Slow Horse Struan Loy in episode 1.
Tom Brooke's JK Coe was then killed by Kyle Soller's assassin character, Jim, in episode 4, while Ruth Bradley's Emma Flyte met a grisly end in a shootout on the beach in episode 6.
However, the most shocking casualty came right at the end of the season, as a huge cliffhanger left fans fearing for the fate of fan-favourite character River (Jack Lowden).
Wondering what happened to River and whether he’s really dead? Read on for everything you need to know about the fate of the character.
What happens to River Cartwright in Slow Horses season 6?
For a minute, it looked like the finale of Slow Horses season 6 was going to end on a triumphant note, with the Slough House crew narrowly surviving Harkness (Hugo Weaving) and Russian assassins Jim (Kyle Soller) and Jane (MyAnna Buring)
But in the final few minutes of the episode, River returned to his grandfather's home where, looking through the window, he realised that former Slow Horses colleague and love interest Sid (Olivia Cooke) was waiting for him.
But as River prepared a romantic gesture for her while she appeared to be upstairs in the shower, he ended up touching a crowbar to move it out of the way.
The character immediately started looking at his hand and collapsed to his knees, breathing heavily – having seemingly been poisoned.
But has River actually died?
Is River Cartwright actually dead in Slow Horses?
Well, it’s possible. In the season 7 preview, Standish asks Lamb whether he’s heard anything from River, to which Lamb responds sarcastically: “Yeah, funny enough, I got a postcard. ‘Weather’s lovely in the afterlife. Sunsets to die for. Love and hugs.'”
However, speaking about River’s fate, in an interview with TV Insider, season 6 writer/EP Gaby Chiappe said: “We don’t know what’s going to happen to him. We know that Novichok has been named, and we know that it has been used within the episode, and we suspect that that’s what it is. And people survive it, but people also die from it. So we don’t know what’s going to happen.”
Chiappe added: “You can hear that Sid’s having a bath upstairs. You can hear the water running. So at some point Sid is going to come down. Is she going to come down soon enough to be able to help River?
"And you have to be really careful touching. It’s a nerve agent that I think permeates your skin. So she’s potentially in danger, but she’s also potentially the reason that — if River does survive, she could be part of the reason that he does survive.”
**Spoiler warning for the Slough House novels...**
What is River's fate in the Slow Horses books?
Fans will be pleased to hear that River does survive in Mick Herron's books, upon which the show is based!
The character is poisoned after touching a doorknob contaminated with Russian nerve agent Novichok at his grandfather’s house but, fortunately, in the eighth book in Herron’s novel series, Bad Actors, we finally learn River's fate.
However, while River survives in Herron's novel, it remains to be seen whether the show will stay true to the source material on this front, and fans will have to wait and see what happens to the character in the show.
Is Jack Lowden leaving Slow Horses?
It's yet to be confirmed whether the actor has left the show or not.
However, with Lowden one of the current favourites to take over from Daniel Craig as the next Bond, it does spring to mind whether the actor’s departure could have been orchestrated in order for him to start filming on the next 007 movie.
And, although this is pure speculation at this point, the timing does seem telling, especially since Bond 26 producer Amy Pascal recently shared that the new casting will be revealed by the end of 2026.
Yet, with filming for season 8 already taking place, perhaps we will see River again...
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