As one door is pushed shut by a grimy MI5 boss, another creaks open — and out steps an oddball private detective who washes in the sink of their office. This week we bid goodbye to Slow Horses series five, but this doesn’t mean it’s time to mothball your television for another year if you’re a fan of stories of outsiders battling against the system.

It has taken Apple a while to cotton on, but finally the Mick Herron Cinematic Universe (HCU: will it catch on?) is born. We’re treated to our first adaptation of the author’s work from outside the beloved Slough House series. And with Halloween upon us, I can say there are no tricks here, only treats.

Things kick off in Oxford as we’re introduced to bored art restorer Sarah Tucker (a fine performance by Ruth Wilson) who by day is undervalued and by night (well, on this first night) helps her financier husband entertain at their home. It’s during dinner with a particularly important and irksome client Gerard (Tom Goodman-Hill) that things take a turn and the evening is cut short by a gas explosion at a neighbour’s house. But this is the HCU (still trying), so that’s not the end of things, it’s only the beginning.

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When Sarah realises that one of the injured children has mysteriously disappeared, she turns amateur sleuth. Her mission: to find the girl, and some answers. By chance, she ends up at the dank Oxford offices of an uninterested private investigator, Zoë Boehm (Emma Thompson), and her husband Joe (Adam Godley). Before long she’s mixed up in Zoë’s world as the pair form an unlikely duo who are up against a lot more than they first thought.

Based on Herron’s first novel and with a snappy screenplay by Morwenna Banks, also a writer on Slow Horses, there’s more than a bit of Slough House about this — from Thompson’s towering performance as the complicated, broken and mysterious Boehm, who has shades of Gary Oldman’s underestimated Jackson Lamb, to the jet black humour and changes in mood and tone.

There’s also Darren Boyd’s dastardly spy chief C, looming over his downtrodden minion Hamzar (Adeel Akhtar) and trying to make Sarah and Zoë look the other way. “So you will tell the chief medical officer to pull his finger out of his arsehole and sign her discharge summary — with his shitty finger if it speeds things up!”

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This is a show that treads a path through spies, lives and unravelling mysteries in such a way as to keep you hooked. Conspiracies grow deeper and plots thicken on a low heat but are punctuated by genuine shocks. And every step of the way we’re reminded of life’s mundanities — the effort of personal grooming, a hand accidentally dunked in a takeaway container and the dog-eared pages of our protagonists’ lives.

While Ruth Wilson’s Sarah may be the way you’re drawn into this adventure, Emma Thompson’s delightfully acerbic Zoë Boehm is the reason to stay. And with three further books in the Boehm series, there’s every chance we could see the Herronverse (that’s better) move into a new gear as viewers get a taste for it. Here’s hoping.
★★★★☆
Episode one and two are available now on Apple TV+, with new episodes every Wednesday

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