!! Spoilers for series six, episode six of Slow Horses. Nothing beyond this episode. Only read on if you've seen it!

This episode opens on the Russian woman from the deadly duo that have been stalking our team all series. She's not as dead as it seemed last episode, and patches herself up in some derelict toilets in an overgrown park. It's a grubby but visually striking scene. The location scouts for this show should be paid vast bonuses. You can never fully trust what you're seeing on screen. We've had several characters believed dead popping back up again but we've had confirmed exits too.

As the finale of the series, there are showdowns aplenty and subplots being wrapped up, but for me, this episode gives us such insight into how the characters will be affected going forward. Twice, River has to break the news about Coe. First to Lamb, by saying "It's just me now." Brutal. And then to the group at the safe house, without having to say a word. The group are visibly shocked and angry, especially Shirley, who was becoming friendly with Coe. Later, she instructs Reece on how to use a weapon, and tells him not to think about the bad things that happen, to push that all down and bottle it up. That's terrible advice, and it's a small moment in a busy episode, but it made me think Shirley's going to have a reckoning at some point soon.

So, the safe house comes under siege. The group, arguing loudly at the kitchen table, immediately start working together when the shots begin firing. Shirley's petrol bombs are very handy as first Harkness and his gang attack, and then the Russian woman creeps in amongst the chaos. Ho calls Flyte a legend as she hurries to provide a distraction and give them room to escape. She's brave and takes out one of the assassins with a well-aimed shot, but sadly is then killed on the beach. It's a shame but I can see how it makes sense narratively. With Taverner saving her job by the skin of her teeth, there's not really any room for Flyte to go back to work.

Louisa is also shot, but survives, whilst Ho tries to be brave but has terrible aim. He ends up being saved by a harpoon wielded by Reece. Later, once the dust settles, we see him practising his aim with a shooting video game. I think Flyte's death affected him more than we realised, and being saved by a harpoon gun will have been traumatic too. Another team member that we need to keep an eye on in future series.

Lamb and Taverner finally work together to sort things out at the higher level. The trust between them, despite the fact they hate each other, is always surprising but gratifying. That he trusts her to follow the plan, despite her previous missteps. That she trusts him so that when he calls and says: "Your holiday home in Suffolk... send help. Send it now", she does it, no questions asked.

And then we get to the end. River rushes to his grandfather's house after hearing that someone is leaving a light on, a gorgeous callback to the last conversation he had with Sid in episode five. But when he gets there, he interacts with some kind of nerve agent, and, in the closing moments of the series, collapses to the floor. He's obviously not dead. It would be a waste of a good character and a terrible send-off for one of the key players in the series. He's clearly going to be fine. But you just never quite know with this show...