Obsession actually opens in a hospital operating theatre, where ‘brilliant surgeon’ William — for some reason you never get a mediocre surgeon in these stories do you? — is just completing the separation of newly-born conjoined twins. What a hero!

However, at Obsession’s compressed narrative pace, it’s not too long before the first hint comes that this apparent paragon of virtue may have other family-splitting talents too. It comes when he attends a political drinks party at which Anna — her identity as his son’s girlfriend not yet revealed — is also present.

Their eyes meet across a crowded cliché and there is instant mutual lust. The first fuck soon follows, and thereafter the action is largely focused on plotting the shortest distance between the duo and their next illicit shag without giving the game away to William’s wife, son Jay (Rish Shah) or daughter Sally (Sonera Angel).

Thanks no doubt to the intimacy co-ordinator, the perfidious pair’s numerous ensuing naked encounters are presented with nudity so tastetful, they might have been recreating famous publicity poses from a coffee-table book of 50 years of soft porn movie posters.

BONDAGE EXTRA-LITE is pretty much all you can expect in the way of BDSM in Obsession (Netflix)

To me, scenes involving light wrist bondage, blindfolding and, er, sensual feeding all evoked half-remembered images from such vintage ‘mainstream’ ventures into S&M territory as 1975’s Story of O or 1986’s 9½ Weeks. Unsurprisingly, by today’s standards, such imagery seems a trifle hackneyed.

Hilarity, meanwhile, definitely isn’t a part of Obsession’s offer — except unintentionally. For this, I refer you to the drama’s most violent sex scene, which takes place between William and a non-consenting hotel bed.

Entering the hotel room his son and his fiancée (William’s lover) have just left, and gripped by passion/jealousy/whatever, our hero sets about rogering the bed they were recently sleeping in. He shags the sheets and pokes the pillows. Please show some respect and refrain from tittering at this very serious scene.

Anyone who has read even the shortest online synopsis of Obsession will have been primed for some unspecified devastating consequences to occur at some point — which they do. The terrible event that changes everything is, of course, held back for as long as possible in the narrative arc. But when it happens, it does actually change the tone of this drama for the better.

Suddenly Obsession is no longer merely voyeur to the playing-out of a high stakes illicit affair. Suddenly the story and the characters in it are brought down to earth with a splattering thud, and everything becomes rather more real and authentic as everyone has to deal with the aftermath.

The final chapter of the drama also presents information about Anna’s history that provides a probable explanation for why she’s the obsessive femme fatale that she is.

Perhaps like me, you might feel more time should have been devoted to unpicking this revelation, and perhaps earlier in the story too. But that is not the way with Obsession, which casually tosses in this crucial bit of back story almost as an afterthought. Don’t blink or you might miss it.

Incidentally no equivalent explanation is offered for Williams’s disgraceful betrayal of his wife and children. Presumably he’s like that because, well, he’s just a bloke, innit. And a feminist too, allegedly. I mean, what more do you want? Nobody’s perfect.

So: did Obsession’s makers achieve their objective of not portraying BDSM sex as bad sex? My answer is yes, they did — but only by largely failing to portray BDSM sex at all.

I can’t imagine anyone who does stick with Obsession to the (literally) bitter end coming away blaming BDSM per se for the dark turn that events take towards the finale. It’s clearly the two lead characters’ obsessiveness itself that seals everyone’s fates — rather than the particular type of sex they’re allegedly obsessed by.  TM