"Uninvited Guests" May Mean No One Gets Out Alive in 'Slow Horses'

Is Slow Horses’ third season its best outing yet? So far, it seems likely. Last week, we had half the season under our belt and felt confident that, thanks to the high frequency of twists, pursuits, and conspiracies, Season 3 was the finest Slough House adventure thus far. With Episode 4, “Uninvited Guest,” our confidence hasn’t been shaken, but we may need to redefine our assessment. As we redirect ourselves towards a blood-pumping third act, it’s clear that Season 3 is the tightest so far – with deeper, festering backstories and resentments shaved off in to deliver the most direct and propulsive thrills. This isn’t a problem – it’s ludicrous fun! – but in boiling down Slow Horses to a science, some of the messy character drama has been compromised.

We begin “Uninvited Guest” with a mirror to last week’s head-to-head between MI5 director Ingrid and Home Secretary Peter Judd, but after Ingrid has learned that Chieftain’s own Tiger Team went rogue and dumped Spider’s corpse outside a classy restaurant (that Judd is an investor in), it’s Judd that’s on the back foot. Ingrid is keen to use Chieftain to clear up their own mess, confident that that’ll be an opportunity to get Judd in her back pocket. 

Diana is thrown by Ingrid wanting to let Sean Donovan into her big, remote archive facility to access the Grey Books, not because she thinks he’ll be able to do anything with them (no conspiracy theory you can find on the History Channel has any truth to it), but because it’s her facility – she hopes it’s not going to backfire on her. Ingrid neatly dismisses her concerns – in many ways, this is an Ingrid episode, as her allegiances and fears finally come into the fray.

Roddy is more practical and less annoying in this episode, which is as big a victory as we could hope for. When scrutinizing the hostage photo taken of Catherine Standish, he notices her nodding towards a column of height marks for children on a nearby doorpost. Aha! This is enough information to cross-examine Chieftain’s safehouses to determine where Catherine is being held. 

Also, Jackson and Louisa are very dismissive over the fact that Spider has been brutally killed, leaving River in a conflicted emotional lurch. It’s a nice feint towards a more complicated characterization for Cartwright, one that Lowden plays convincingly for the few moments before Louisa tells him not to overthink it. If only Spider had been offered a chance at such complicated feelings, we might have an unlikely but satisfying partnership on our hands! Alas, he was a bastard til the grave.

Back at the safehouse, the Chieftain agent whom Sean kidnapped manages to escape (hey, the private sector isn’t completely useless!), and Sean is very candid with Catherine about his late partner, Alison. She discovered some intel that made her turn on MI5, and her assassination was covered up as a suicide, which has put Sean on the warpath. Catherine balks at the idea that MI5 would ever off one of their agents, a heavy-handed and ironic nod to what the audience knows about Charles Partner’s killers.

Speaking of which, River is briefly drawn away to see his grandfather David (Jonathan Pryce), who has been denied entrance to his upper-crust men’s club because, as River reminds him, he left it a good while ago. Yep, David’s memory is slipping in old age. Again, a more sensitive, non-thriller plotting scene is welcome for River, and Lowden makes an excellent sardonic, bitter match for Pryce.

River tries to pass on this emotional sensitivity to Louisa; the pair share a sweet but stunted conversation about grieving while on active field duty, nicely reminding us how Louisa has quietly established herself as one of the best characters. As Roddy and Jackson head off to the newly identified safehouse (admittedly a great dynamic, especially as Roddy gets to gloat when Jackson sincerely tells Marcus and Shirley to face that they are fired), River and Louisa meet Sean and one of his teammates at the archive, where after some overwritten banter they’re directed to the Grey Books.

But Sean isn’t after the Grey Books, but the location of the file Alison was prepared to leak. River and Louisa realize they’re powerless to stop him just as Ingrid learns of Sean’s identity – and the fact that his teammates are also connected to Alison. As Nick Duffy (Chris Reilly) and Hobbs (Chris Coghill) arrive with a sheepish Chieftain battalion ready to arrest Sean upon Catherine’s release, they get redirected orders from Ingrid – kill everyone in the archive, no one is allowed to get out alive. Duffy et al. are only too happy to oblige. 

“Uninvited Guest” ends on a dramatic cliff-edge, as Jackson heads towards Catherine and the rest head towards a gun barrel; even if the messier edges of this show’s character writing have been clipped, it’s hard to deny the impact of its pristine and pacy thrills. Roll on the carnage.