'Slow Horses' Gets Stuck "Cleaning Up" in Season 3's Penultimate Episode

It’s Siege Week on Slow Horses. “Cleaning Up” dials up the pressure on Slough House, who have once again found themselves unanimously at the center of a clandestine MI5 coverup, leaving only one episode left for MI5’s most productive screw-ups to do their classic maneuver of a) stopping rogue agents doing something calamitous and evil and b) avoid being murdered in the process. With the majority of the slow horses pinned under gunfire when the credits roll, Season 3’s final cliffhanger takes the biscuit for “Most Likely for Our Beloved Characters to All Be Killed” out of any thus far.

With Louisa and River being violently flushed out of the archive facility, Marcus and Shirley taking the initiative to rescue them, and Jackson and Roddy on route to save Catherine before Duffy and Chieftain execute her, it’s easy to forget that Slow Horses Season 3 takes place over, at most, two days. This is par for the course with the series – both Seasons 1 and 2 kicked into overdrive around the halfway mark and then unfolded in less than 24 hours. And yet, the insistence on slick, tight, economical storytelling that Season 3 prioritizes still makes this Slough House outing feel a touch slighter than before, even if the raised stakes deliver a seriously entertaining package.

Diana Taverner has barely left her office this season, which hasn’t changed with “Cleaning Up.” It’s calmly (anti-climatically?) revealed that Taverner is behind, well, everything – she set up Sean, Webb, and Chieftain to find Alison’s to-be-leaked Footprint file to oust Ingrid and replace her as First Desk. Ingrid signed off on a new piece of tech, one that wirelessly hacks encrypted computers, but the device didn’t work, and loads of international agents were injured and endangered. Alison was assassinated for the simple crime of finding out what the MI5 chief had done.

There’s no sense of moral compass in Diana; Ingrid’s enemies and misdemeanors are just chess pieces to be used for her benefit. While it’s clear Slow Horses had limited time with Kristen Scott Thomas compared to previous years (they make sure they get good use out of that one office!), seeing her share whiskey with her simmering rival and ponder about which of them will come out on top feels appropriately Cold War espionage-y, especially in an episode mainly consisting of gunfire.

Louisa and River are drawn deeper into the archive facility as Sean and Alison’s brother Ben (Charlie Rowe) hunt for the Footprint file that Taverner anonymously tipped them off about – but the facility’s nerdy, overeager clerk Douglas (Sion Daniel Young) pulls River away to let him know a small Chieftain army, led by Chris Duffy, has arrived at their door. River is initially sure that they mean them no harm, but seeing them take out their cameras and block all but one exit makes it clear they’re doing a siege. Plus, doors being blown off and guns being fired inside are a dead giveaway.

River gets a voicemail to Slough House, informing Marcus and Shirley that they need assistance just before the facility’s phone lines are cut. River escapes Duffy’s gunfire, but Douglas is captured – and about to get away scot-free until he mentions he knows of Ingrid’s connection to the facility. Tough luck, buddy. Duffy kills him. By this point, it’s clear there’s no going back for Nick or Hobbs – they are fascistic muscle that have gone too far in service of MI5.

Meanwhile, Catherine remains at the safe house with Alison’s sister Sarah (Eliot Salt) and really overplays how shocked she is that MI5 would assassinate their own agents, making sure to note that this would never have happened when Charles Partner was in charge (hint: I wonder if she’s going to find out Jackson killed Charles for being a traitor!!) Anyway, we leave the safe house with Hobbs arriving to permanently dispatch Catherine, with Roddy lurking nearby ready to pounce.

Shirley and Marcus come to River et al.’s defense with, err, automatic gunfire. It turns out Marcus is a bit of a private security nut, having been offered a position with the Dogs, but he nobly turned down Duffy’s offer on account of him being a “thug.” It’s a bit weird seeing two of Slough House’s more hapless agents pack massive machine guns, and you wonder if something has been lost from the days when pencil pushers had to unceremoniously evade being swallowed by the faceless bureaucracy of MI5 interrogations back in S1.

Sean refuses to escape the facility as Chieftain gunmen close in on them, discovering Footprint at the last minute – but it seems too late. Ben is shot trying to grab a handgun, and the episode ends with a slow-motion grenade blast, burying River in an avalanche of files and shelves. “Cleaning Up” makes more of a mess than the title implies, and it’s fun enough to distract us from the fact that these episode cliffhangers are a bit artificial – the plot has not been substantially altered by our characters; the same tensions are just growing in severity. And yet, they’re effective: how will they get out of this jam next week?