"Slow Horses" is the best show on TV. Don't just take it from me, even though I ranked it as the top show of 2023. Our streaming editor Kelly Woo called it "the best show you're not watching" after season 2 and the third season initially scored a perfect 100% on Rotten Tomatoes (it's since dropped to a mere 98%). Season 3 even earned nine Emmy nominations, including Outstanding Drama Series.
Believe me now? Good, because Apple TV just dropped an explosive new trailer for season 4.
This British spy thriller about a band of rejects led by a washed-up spymaster has never shied away from gripping action, a fast-paced story, a sprinkling of violence and a heavy dose of Gary Oldman being an incredible actor. This latest trailer for "Slow Horses" doesn't shy away from those things either.
But after watching this latest trailer, the show's writers may have cranked things up to 11 for season 4. And I'm not just saying that because there's a car bomb that goes off in the first 30 seconds of the trailer. This trailer is loaded with moments emblematic of what makes this show great, including River Cartwright (Jack Lowden) comically trying to escape danger on the world's slowest bicycle and ending the trailer with a callous, off-color remark from Oldman as washed-up spy Jackson Lamb.
'Slow Horses' season 4 introduces a bad, bad man
Aside from showing us more of what the show already does so well though, the most important thing this trailer does is give us a look at this season's bad guy.
Each season of "Slow Horses" is based on a different book from Mick Herron's "Slough House" series. That is why each show is just six episodes long and why, despite character arcs that stretch over the entire series, each season brings a new crisis that is contained within the season.
This season is no different. Season 4 is based on the "Slough House" book "Spook Street" and introduces Hugo Weaving as the villainous Frank Harkness. While our band of misfit spies may not have interacted with Harkness directly, this new trailer leads us to believe they've still managed to upset the guy.
This is bad news, because according to River's grandfather, the former MI5 legend David Cartwright (Jonathan Pryce), Harkness is "a monster" that created a death squad in the past. Based on what we've seen in this new trailer, Harkness has put together an assassination squad again and is ready to send a message. Given that Jackson Lamb says that one of the Slow Horses is killed during season 4, it looks like Harkness manages to send his message with devastating effect.
"Slow Horses" season 4 premieres Sept. 4 on Apple TV Plus.
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