I’ve only just hitched my wagon to Slow Horses – but I’m loving the ride

Although peak TV has officially peaked, there is obviously still far too much television. My job involves watching as many TV shows as I possibly can, and yet sometimes it feels as though I can only consume the very tip of the iceberg. Just when I think I’ve got a good handle on things, someone will send me an email saying, “Lou Diamond Phillips gives the performance of a lifetime in Not Without My Carrots, exclusive to the new Google Maps streaming platform, starting at just £75 per month,” and I’ll be back to square one.

What I’m saying is that we’re all bound to miss stuff from time to time. Even so, I must confess to feeling a little bit silly about having only just discovered Slow Horses .

In my defence, I knew Slow Horses existed. I just didn’t watch it because of good old-fashioned obstinacy. There are too many streaming platforms, I decided, each too greedy to take a bite out of my wages. And so, as of a while ago, I started pretending the new ones didn’t exist. BritBox? No thanks. Paramount Plus? Never heard of her. Apple TV+? Purely for how ungainly it looks with a question mark after it, I’m out.

But I’ve caved. I’d heard too many good things about Slow Horses. It’s stupendously reviewed; it has an army of fans. A tweet I saw recently said that, had it been broadcast on BBC One rather than Apple, Slow Horses would be a Line of Duty-sized hit. Now that I’ve seen it, I can’t disagree.

Clearly, the main draw is Gary Oldman. The scale of Oldman’s talent is so vast that, whatever you watch him in, you sense that you’re witnessing his definitive performance. But here it truly seems to be the case. His Jackson Lamb, head of a division of spies that have all been demoted to a grotty purgatory, is sensational. Weary, rude and flatulent, he’s a walking clutch of defence mechanisms designed to prevent anyone from ever getting close to him. And my goodness, he’s funny with it. Towards the end of the first series, there’s a big set piece that involves him singing along to a song by the Proclaimers at gunpoint, and I’ll be damned if it isn’t the most joyous thing I’ve seen on television in an age.

Incredibly, almost everyone else is just as good. Jack Lowden , playing the nearest thing to a protagonist, is able to undercut his heroism with precise comic timing. Rosalind Eleazar, who ends up carrying the bulk of the show’s emotional beats, never gets dragged down by them.

Related: Saskia Reeves: ‘Where else could you find yourself in a taxi between Jonathan Pryce and Gary Oldman?’

I’m tempted to say that Saskia Reeves is the best of the lot, however, purely for how comprehensively she disappears into her role. Her character is brittle and buried and resigned, and Reeves inhabits it completely. There’s a lot of talk about Slow Horses being a sleeper hit – the fact I’m only coming to it now seems to prove that – and so hopefully in time Reeves will get the awards recognition she deserves for it.

Which isn’t to say that the show is perfect, of course. The second season doesn’t fit neatly into the series as a whole: everything about it is a little bit off. The Slough House team are kept apart for most of it; the narrative strands come together too late; the tone is weirdly cosy; even the lighting is a bit too clean and bright. It’s like a bizarro version of Slow Horses that was commissioned and aired by ITV3. Had I been watching episode by episode like the rest of the world, this might have been the point where I ducked out.

I’m glad that isn’t the case, though, because the show is absolutely motoring now. Seasons three and four have a newfound swagger, as if everyone involved knows that what they’re making is incredible. More seasons are to come – the fifth was greenlit in January – and Mick Herron is able to churn out Slough House novels and novellas at such a clip that the show won’t be short of source material for a very long time. And in Will Smith, who has written comedy for The Thick of It and a thriller in his extremely good 2015 novel Mainlander , it has found the perfect showrunner.

There’s a danger with longevity, of course. Writing Jackson Lamb alone must be a tightrope: with every reveal that he is slightly nicer than you expected, there’s a risk that his sharp edges will gradually erode and transform him into farty Father Christmas. But that’s a worry for another time. Slow Horses is one of the best things I’ve seen in a long time. Don’t wait as long as me to discover it for yourself.

• Slow Horses is on Apple TV+ now