Slow Horses Got the Chance to Get Comfortable

Photo: Apple TV+

Spoilers for Slow Horses season-four finale “Hello Goodbye� follow.

It’s baffling that more TV series have not adopted the Slow Horses model of storytelling. Years ago, when cable platforms and premium channels first started distinguishing themselves from the 22-episode network season, the Slow Horses structure seemed like the future of TV. It uses shortish self-contained seasons that draw out multiple plot threads, and eventually they all collide into a catastrophic wallop. Character development builds across the series, which means big moments of discovery and internecine power struggles have more oomph as time goes on. Even if one season wobbles, the next season offers enough of a fresh start. The whole show might be building to one big final outcome, but each installment stands alone enough that its finale does not become a make-or-break test for the series.

It’s a model that can help a show hold onto an audience even when viewers have differing opinions about what that show does best. Depending on your preference, season four of Slow Horses is either excellent, fun despite some quibbles, or “not my favorite, but still pretty good.� For people who like the Tinker Tailor mode of behind-the-scenes politicking and the occasional desperate dash down an alleyway, season four has been a happy return to form. Viewers inclined to action-thriller mode may have found season four underwhelming compared with season three, with fewer ticking timers attached to explosive devices and fewer gunfights involving crouched figures behind chest-high walls. But it still checks all the boxes of what a Slow Horses season should do. More than once, River Cartwright (Jack Lowden) breaks into a desperate sprint to either catch someone or evade someone else. Jackson Lamb (Gary Oldman) appears to know more than he’s saying, especially about some mysterious thing that happened in the ’70s that everyone tried to forget about. Diana Taverner (Kristin Scott Thomas) holds it all together while also stabbing a few people in the back. It’s the show being the show — fresh but familiar — and that’s exactly the point: Even the worst season of Slow Horses is still a perfectly enjoyable season of Slow Horses.

There is one significant shift from previous seasons, to be fair. Rather than just a bad guy’s big terror plot to destroy the United Kingdom, season four is pegged to the dramatic reveal of River Cartwright’s family history (which, yes, fine, is also connected to a bad guy’s big terror plot to destroy the United Kingdom). River has been a de facto protagonist from the start, and life-threatening spy folderol has always been at least a little personal, as his retired spymaster grandfather has featured prominently in the show from the beginning. But season four’s decision to give Cartwright an Empire Strikes Back twist is a change for a series that’s so far avoided obvious hero’s-journey arcs. By the end of the season, Hugo Weaving’s Frank Harkness, the series’s new mysterious unstoppable baddie, is revealed to be River Cartwright’s father!! And Cartwright indulges in a few moments of the kind of perplexed introspection that Slow Horses rarely pauses to provide.

Some elements of this plotline are baldly absurd. The big reveal is easily apparent at least two episodes before the show finally pulls away the curtain, and the underlying mechanic for the whole thing is even worse. Cartwright discovers that his entire life is the result of Harkness’s secret French paramilitary compound, an organization designed to raise children into super soldiers. Just in case anyone reading this happens to be in the middle of a screenplay: Children raised to be super soldiers is a premise that needs to be shelved for a while. It’s trended more toward sci-fi recently (Umbrella Academy, Stranger Things, The Boys, Game of Thrones’s Unsullied), yes, but the trope is so well known it’s hard to muster the shocked disgust Slow Horses seems to expect as Cartwright pokes his way around an abandoned schoolroom/military-training ground.

Even with those detractions, it’s still Slow Horses — it knows its job, and it does that job well. A different show could easily fall down the well of River Cartwright’s identity spiral, narrowing in on his increasing desperation and crisis of self-doubt to the exclusion of everything else that makes the show work. Instead, Cartwright receives this shocking news with consternation and dismay; then within moments, he’s back to furrowing his brow as he leaps over a barricade inside a train station. Taverner’s in peak Mean Mommy mode, demoted to Second Desk but still covering up MI5 mistakes by sternly and efficiently topping the buffoonish new First Desk (James Callis) from the bottom. Corruption within the organization, after all, is as much a part of the show as Jackson Lamb’s slovenly habits and horrible diet. And when Marcus doesn’t survive the last firefight, it’s as tragic and surprising and yet grimly status quo as Slow Horses has ever been, especially because Marcus and Shirley have now had multiple seasons to develop their needling, supportive, cranky-partner rapport.

The series resolutely refuses to become cuddly or sweet; its band of misfit toys will never coalesce into a functional group of outcast avengers, and when they die, their selfishness and imperfections — their unpleasant humanity — make their deaths all the more upsetting. It’s easy to weep for martyrs who never seem like real people, to cry for them and quickly dismiss them, because they were never all that real to begin with. The Slough House spies are too prickly and vulnerable to be written off so easily.

And yet, the Slow Horses model has become an exception rather than the rule. Shows like House of the Dragon, The Rings of Power, or The Penguin squeeze themselves into the leftover spaces within well-known IP, and as a result, their stories feel boxed in from all sides, stretching and sliding to fill space or to dodge ground that’s being covered somewhere else. Anthology series like the ones dotting Ryan Murphy’s oeuvre build a show over a season but lose any of the slow-burn relationship chemistry that gives Slow Horses its emotional oomph. Few non–Emily in Paris–level Netflix shows get the chance to exist beyond a third season, denying them the opportunity to exhibit a consistent four-season run even if they wanted to. Slow Horses’s success is not an Apple TV+ thing, either — Apple shows with longer runways like Ted Lasso and For All Mankind have had just as uneven and half-baked seasons as long-running series from other outlets. But Slow Horses has succeeded by finding a comfortable, familiar, well-proven storytelling formula and doing it well, focusing on character development, cohesion, and making every episode count. It’s not rocket science, but it is why Slow Horses, four seasons in, is more than solid. For TV in 2024, consistency like that feels miraculous.