‘Slow Horses’ season 5 starts with a bang and I can't stop thinking about the shocking premiere

I've long lauded "Slow Horses" as being one of the best shows on TV, if not the best. So "Slow Horses" season 5 has a high bar to clear to live up to my expectations for the Apple TV Plus British spy thriller. Unsurprisingly, not only did it clear that bar, but the season 5 premiere might be setting up the show's best season yet.

For those of you who haven't seen the "Slow Horses" premiere yet, here are all the details I can give you before getting into spoilers. Season 5 adapts Mick Herron's 2018 novel "London Rules," the fifth novel in the "Slough House" series. It centers around a series of terrorist attacks, including a mass shooting we see discussed in the official season 5 trailer and MI5 second-in-command Diana Taverner (Kristin Scott Thomas) has put Slough House in lockdown. The reason for this lockdown? Both she and Jackson Lamb (Gary Oldman) are suspicious about Roddy Ho's (Christopher Chung) dating life (namely, that it exists), and they both think his new girlfriend could be involved in the terror attacks hitting London.

So, if you've seen the premiere, read on. Otherwise, stop what you're doing, queue up the first episode of "Slow Horses" season 5 on Apple TV Plus, and come back here in about an hour.

Spoilers ahead for "Slow Horses" season 5 episode 1

'Slow Horses' doesn't start slow — and it doesn't let up

When I talk to people about what makes "Slow Horses" so good, it basically boils down to two things. First, the writing is incredible, with perfect pacing, scathing dialogue and the ability to wrap everything up in six episodes without you wanting more (or less). Second, it's got Gary Oldman playing a British spymaster.

Unsurprisingly, season 5 doesn't mess with that formula at all. The pacing of this season is already excellent. Other shows might have saved a terrorist attack for later, but this show uses it as the inciting incident for the season. By the end of the episode, we already know that something more nefarious than a mass shooting is afoot, and we know that Roddy and his girlfriend must somehow be involved. We're not wasting time beating around the bush.

There's plenty of scathing writing in this first episode as well. My favorite moments from the episode are:

• Shirley Dander (Aimee-Ffion Edwards) asks Lamb if he wants his door, which consists of only a frame after the events of season 4, open or closed.
• Shirley calls River Cartwright (Jack Lowden) "profoundly asexual" at the nightclub where they are tailing Roddy.
• Lamb has his recovering alcoholic assistant, Catherine Standish (Saskia Reeves), saved in his phone as "Old Soak," which refers to someone who is often drunk.

Clearly, it's a great episode for Shirley, who has a meaningful role in this season premiere. It's she who thinks the Abbotsfield shooting is connected to someone almost running over Roddy with a Sprinter van ... and it's she who jumps from a balcony onto a dancefloor to assault a man.

But it's not just an important episode for her. Louisa Guy (Rosalind Eleazar) is revealed to be leaving Slough House and the service after the past four seasons of trauma have finally become too much for her. She's also leaving River behind, who makes an ill-advised move on Louisa, though he isn't over the events of season 4 that revealed his father (Hugo Weaving) is a killer and his grandfather (Jonathan Pryce) has dementia. Rather, he thinks he's over it, but literally nobody else does, and they aren't afraid to tell River.

Could Louisa be gone from 'Slow Horses' for good?

Another reason that "Slow Horses" is one of the best dramas from the best streaming services year in and year out is that it's not afraid to kill its darlings. We lost Olivia Cooke from the cast after season 1, Min Harper was killed in season 2 and Marcus Longridge was killed in season 4. That's just the people from Slough House; many other cast members have come and gone, with some even to return, whether because they failed to play by Moscow Rules or because they failed to play by London Rules.

At the end of this episode, we see Louisa leave Slough House and Rosalind Eleazar leave "Slow Horses," and there's a real chance both are gone for good. Aside from Lamb (Oldman), River (Lowden) and Taverner (Scott Thomas), everyone and anyone is fair game in this show, and I think Louisa won't be returning to the screen.

Of course, this show also keeps you guessing right until the very end, so we'll need to watch "Slow Horses" season 5 all the way through to see if she ever comes back — or if anyone else is leaving with her.

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Malcolm McMillan

Malcolm has been with Tom's Guide since 2022, and has been covering the latest in streaming shows and movies since 2023. He's not one to shy away from a hot take, including that "John Wick" is one of the four greatest films ever made.

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