In case you needed it yourself, Lamb (Gary Oldman) and company start off Slow Horses season 4 episode 4 with a quick recap of everything that's going on. They determine the man who's after Sam Chapman (Sean Gilder) is a pro, but Chapman doesn't recognize him. When Lamb asks him about Lavande, it clicks for Chapman: this is all about Les Arbres, which houses a team of professional killers. He doesn't want to be debriefed at the Park though, worried they'll lock him up for whatever he did, so instead they take him to Slough House.
Speaking of those professional killers, their leader Frank (Hugo Weaving) meets with his employer: royalty from an unnamed Middle Eastern country who is none too pleased about how Westacres went down. While Frank admits they messed up, his employer simply wants to tie off all loose ends rather than risk the British government finding out about their involvement — meaning killing Frank. Frank says others are already aware something is up, but he can kill them to close the loop. His employer gives him until midnight. So now there is a target and a ticking clock on both Chapman and David Cartwright (Jonathan Pryce).
Read on for a full breakdown of Slow Horses season 4 episode 4.
The history of Les Arbres
As Lamb and Chapman arrive at Slough House, an MI5 car is waiting. Lamb checks it out, discovering Taverner (Kristin Scott Thomas). She's got a general idea of what has happened but has two questions for Lamb: why would someone want to kill David now and where is River (Jack Lowden)? Lamb gives her the bare minimum of information and needles her when he realizes Flyte (Ruth Bradley) hasn't been keeping her up to date on everything going on. She tells him to inform her if either of the Cartwrights shows up.
Inside Slough House, Standish (Saskia Reeves) is waiting and like everyone else is confused by JK (Tom Brooke), though she thinks his fidgeting fingers are his attempt to block something out. She then tells Lamb that David got out. Since he wanted to speak to First Desk, she sent Louisa (Rosalind Eleazar) to keep an eye out for him at the Park. Lamb then tells Standish to join him on the debrief with Chapman.
Chapman explains he went to France once for David, taking a car that was packed full of guns, ammunition, explosives and IDs — MI5's cold bodies. He brought all this to Les Arbres to exchange for a woman. In a flashback we see a young Frank, though Chapman doesn't know his name, only calling him a "scary f***er." As the young woman is leaving, Frank whispers something into her ear that we don't hear, she then slaps him across the face before getting into the car. He recalls she didn't say a word the whole way back to England, then gave Chapman the slip as soon as she could. However, what he really thought was strange was that David didn't seem to care.
With this intel and Standish saying David wanted to speak with First Desk, Lamb pieces together he isn't heading for the Park, but "the old building," the previous headquarters of MI5.
The race to the Cartwrights
Lamb isn't the only one to figure this out. After getting a talking to by Taverner that if she keeps any more information from her Flyte will be fired, Flyte gets a call from "the old building." It has been converted to a hotel but they are still aware enough to let MI5 know when David shows up asking to speak with First Desk. Flyte tells the concierge to keep an eye on David until they get there. So it's a race to the old building as Lamb, Chapman and Standish try to beat Flyte there (who on the way appears to recognize Louisa standing outside the Park).
Meanwhile, Taverner tells Claude (James Callis) they found David and she'll debrief him when he gets to the Park. However, Claude has a surprise for Taverner. He reveals Giti (Kiran Sonia Sawar) got more info on the cold bodies and found Adam Lockhead, the alias used by River's doppelganger. He's angry she kept this from him and says they'll have to have a complete and public investigation into the situation. Taverner calls him a fool, saying their only priority is to find out if another bomb is going to go off, opening themselves up to the public won't do any good. One thing did come of this for MI5 though, as Giti notifies them that Adam Lockhead's passport is on its way back to London, meaning River is on his way back. Taverner calls Flyte and tells her to split her teams to go after both David and River.
Lamb, Chapman and Standish arrive first at the old building. Chapman goes to talk to David while Standish attempts to figure out how to distract the Dogs on their way; Lamb waits in the getaway car. David doesn't immediately recognize Chapman, but even when he does he won't be moved, saying he is waiting for First Desk.
As the Dogs arrive at the hotel, Standish sets off the fire alarm to cause confusion. It works, as the agents walk right by David and Chapman to speak with the concierge. However, when the concierge points out where David was sitting, he and Chapman are gone.
With David in the car, Chapman says he is going to break off, grab his flight fund and head out of the country to avoid prosecution from the Park. However, he's not out of the woods. We saw earlier Frank meet with his assassin, Patrice (Tom Woznickza). He also knows where Chapman stashed his flight fund. He's able to sneak up on Chapman, beating him to get info on where David is and then presumably finishing what he failed to do previously and killing him.
River's unwelcoming return
On the train, River continues to look at the picture of the mural at Les Arbres on his phone; there's something about it that clearly has him curious.
As the train arrives, Flyte and her team race to intercept River. Frank is also at the station, but hangs back as he spots Flyte. To figure out how the Park is ahead of him, Frank plans to go through the same channel they used to get David's address originally.
River evades Flyte and her men on the train platform, but they eventually track him down and give chase through the station. River is only able to elude them when he slips onto a metro car at the last second, with the door closing on Flyte and the other agents' faces. Still, Flyte believes she knows where River is going: home.
Home being David's house, where River is able to sneak in. He finds a box of pictures in the house, including drawings that are similar to that of the mural, causing him to say "f**k me." That same sentiment can be applied when he hears Flyte and her team arrive at the house. However, River is able to hide in the attic, seemingly avoiding them. That is until he drops down and finds Flyte waiting for him.
New episodes of Slow Horses season 4 premiere Wednesdays on Apple TV Plus.
