Slow Horses is an old-school British spy thriller done right

Slow Horses doesn’t reinvent the spy thriller because the spy thriller doesn’t need reinventing. Based on author Mick Herron’s award-winning crime novels, Apple TV Plus’ no-nonsense espionage drama—streaming two episodes on April 1, then weekly after that—gets back to basics with a six-episode kidnapping conspiracy that’s played straight and never lets up.

Instead of distracting with high-tech gadgets, CGI-laden chase sequences, and/or inexplicable cocktail parties, Slow Horses relies on tried-and-true tension-builders to get the job done. If you want an excellent slow-burn surveillance mystery delivered point-blank, this is it. It’s produced well, written better, and manages to maintain that one-two punch throughout.

Gary Oldman stars as Jackson Lamb, a cynical intelligence agent tasked with overseeing the ragtag crew of Slough House, an administrative purgatory where MI5 rejects are left to languish. Enter River Cartwright, played by an exquisitely cast Jack Lowden, who’s stuck there after botching a critical training mission that left dozens “dead” and hundreds more “injured.” This surprisingly public debacle is made only more embarrassing by the shadow of River’s retired spy grandfather David Cartwright (a sparingly used Jonathan Pryce) whose legendary track record precedes even his grandson’s famed failure.

Eight months into River’s so-called Slough House sentence, the discouraged protagonist is surrounded by fellow “Slow Horses”—the series’ title doubles as a derogatory nickname—and hating it. We’re haphazardly introduced to agents Sid Baker (Olivia Cooke), Roddy Ho (Christopher Chung), Min Harper (Dustin Demri-Burns), Louisa Guy (Rosalind Eleazar), and Catherine Standish (Saskia Reeves) in an understated premiere episode that could just as well set up a workplace comedy.

But when British Pakistani student/aspiring stand-up comic Hassan Ahmed (Antonio Aakeel) is abducted by a group of masked men who threaten to kill him on live television, Lamb, River, and a gaggle of other MI5 misfits find themselves ensnared in a political plot that positions the Underdogs/Slow Horses (Under-dorses? Slunder-hogs?) as have-to-be heroes. Even Lamb is pulled into the fray, reluctantly leading agents he doesn’t like or trust.

Where less secure spy sagas double-down or double-cross to make up for lacking heart, this show dares to trust that those along for the ride will be just as compelled by slow-broiling realism. The action swells and shrinks to match what “feels right” for the scenario, while never losing focus on the peripheral elements needed to bring a high-powered chess game into focus.

As such, we learn about the Slow Horses efforts just as we do the inner-workings of MI5’s more illustrious HQ, headed by the steely Diana Taverner (a terrifying and flawless Kristin Scott Thomas), and the fugitive criminals holding Hassan hostage.

The dramatic payoffs are stupendous, too. When you think a mission will go right, sure, there’s a chance it really will. When you fear an undeserving character might die, they very well may. Yet somehow, despite the occasional predictabilities, Slow Horses remains an edge-of-your-seat watch—with a killer finale that’s gut-wrenching start to end.

Of course, the performances best sell this style. Oldman, who at 64-years-old has won or been nominated for most major awards, shines exactly as you’d expect. Lowden plays the ambitious hero with similar success.

But the most notable performances come from Cooke, who dazzles much like she did in Bates Motel, and Brian Vernel, who plays one of the villainous tormentors and steals key scenes episode after episode. If he doesn’t quite match Oldman or Lowden, that’s only because he’s one of the bad guys. His henchmen, played by David Walmsley and Stephen Walters, provide ample support.

Slow Horses’s first season is chock full of characters, lines, and moments that will work brilliantly for fans of spy thrillers—not gritty spy thrillers, not action-packed spy thrillers, but straight-laced, classic, by-the-book ones. There are more episodes on the way (and more books to adapt). But for now, this conventional addition to an already crowded genre counts as a confirmed kill.