A youngish couple leave London and drive off excitedly to make a fresh start in more rural surroundings. They demonstrate their happiness by laughing all the way to their new town, where a cheery sign on the outskirts reads: ‘Welcome to Midwich’. So what could possibly go wrong?

In fact, even for viewers unfamiliar with John Wyndham’s famously spooky 1957 novel, from which Sky Max’s modern-day version of The Midwich Cuckoos has been adapted, it’s clear that something soon will. After all, a pre-credit sequence, set five years later, had shown the same couple cowering in fear before their five-year-old daughter. For now, though, while they marvelled at the idyllic views, we were efficiently introduced to their neighbours, before Thursday’s first episode went about its main business of increasingly unsettling us.

In my last column I reviewed Conversations with Friends, of which the phrase ‘slow burn’ has been much used in its traditional sense of ‘a bit boring’. Here, in a rare twist, the slow burn works precisely as it’s meant to: by quietly but insistently cranking up a feeling of anxiety.

So it was that the weirdness began in an understated, even slightly hoary way, with people’s lights flickering on and off. But fortunately worse was to come when mobile phones lost their signal, Midwich became electronically cut off from the outside world and one by one, with varying degrees of theatricality, the townsfolk collapsed unconscious to the ground.

There were, mind you, two characters who escaped this fate by the simple means of not being there at the time – and, as luck would have it, they were played by the biggest names in the cast. Dr Susannah Zellaby (Keeley Hawes), a child psychologist, arrived back from London to find Midwich cordoned off, leaving her in a frenzy about the troubled 23-year-old daughter who lives with her. Paul Haynes (Max Beesley) is the local policeman whose pregnant wife also featured among the comatose – and whose state of mind wasn’t eased when the security services showed up to throw their weight unhelpfully about.

Then, 12 hours after they’d fallen down, everybody in the danger zone suddenly woke up – which might have signalled a return to the old normal, except that all the women of child-bearing age are now not just pregnant but pregnant enough to be showing.

And in this, I’d suggest, they’re not unlike the series itself at the end of episode one. Judging from that pre-credit sequence, the real body of the show is still to come. Yet, with a large cast of characters neatly established – and the unforced parallels with our current worries about the world no longer feeling under our control deftly taking shape – The Midwich Cuckoos definitely seems on the brink of delivering something both mysterious and special.

And still with Sky, Once Upon a Time in Londongrad is looking pretty good too, especially if you can overlook the shameless self-promotion of BuzzFeed that accompanies the main story.

Not that this is always easy. The first of Tuesday’s two episodes opened with Heidi Blake ‘Senior Investigator BuzzFeed News’ (and the series’ consulting producer) explaining how she used to work for newspapers ‘with declining circulations’. But that was before she was approached by BuzzFeed, which she’d mistakenly thought was all about clickbait rather than unrivalled news reporting.

The way Heidi told it (not entirely convincingly), the starting point for her team’s terrific scoop came when she got a phone call out of the blue summoning her to a posh London address – and was, she claims, startled to discover the door being opened by Michelle Young, the ex-wife of Scot Young, who’d fallen to his death from a fourth-floor window in 2014. Luckily, our Heidi already happened to know a lot about the Youngs’ finances from their divorce proceedings, and so was well-equipped to investigate further when Michelle suggested that Scot had been murdered by his shady business contacts.

Before long, Heidi had unearthed Scot’s close connections to several London-based Russian billionaires for whom he apparently laundered money. This, in turn, led to a rather impressive summary of the rise of the oligarchs under Boris Yeltsin – and their fall from grace under Vladimir Putin: a man they’d helped to make Russian president in the mistaken belief that he’d let them continue to exert political influence.

Annoyingly, too, from what we saw the BuzzFeed team do seem to be right in their continual boasting about what a great job they did gathering documents, videos and contacts. By now, the fundamentals of the oligarchs’ tale may be familiar enough. But by laying out chapter and verse so assiduously, the series is a jolting reminder of how much they, and Putin, got away with for so long. In short, this is a smug programme with plenty to be smug about.