It was, if only occasionally, murder but there is no mystery as to why Taggart is viewed with deep affection 40 years after its birth.

The celebrations and remembrances that accompany this anniversary were captured beautifully in The Herald this weekend, generating more clicks than a flamenco troupe on speed.

Taggart was loved. Taggart is obviously loved still. Why? 

Its popularity is thought to be tied to proximity. It was of and about Glasgow. In the manner of that famous line of Spartacus, we are all Taggart, or at least, recognised him and where he patrolled.

Its enduring power, though, is driven by more than parochialism, otherwise why were viewing figures in England so high and how did STV sell a Glasgow police procedural all over the world?

There were wonderful peculiarities to Taggart. Yes, it was gently thrilling (it was a simpler time) to see places you knew come to life on the box in the corner of the living room.

Yes, it was undeniably Scottish. There was an episode written by a Dunfermline fan that had characters’ names taken from a Pars cup final team. Colin McCredie, a St Johnstone fan, inserted a Saints mug into one of the scenes.

And, yes, it is absolutely smashing to watch on STVPlayer and trace the early steps of some talented actors (Alan Cumming and Mark Bonnar, in particular) and the assured strides of the more experienced (Annette Cosbie and James Cosmo).

Read more: Taggart: We bring stars back – after 40 years

But it had substance. The writing was generally excellent. It was funny in that Glesca way when the best lines are said from the side of the mouth, particularly one with a fag hanging from it.

It even had a political dimension. STV’s tangles with network television over funding and air time will be familiar to a later generation’s wrestling with reserved powers.

Its rise and demise was also a story of how television changed. 

Taggart prospered as a single story told over one episode. Television successes now may have the single story but they unwind over a series of episodes. Ironically, this was how Taggart had started, with the three-episode Killer. The format of individual episodes killed it but only after the best part of 30 years. 

However, Taggart both inspired and was born of the culture of the times. Taggart was Tartan Noir on the screen. Val McDermid, Ian Rankin, Liam McIlvanney and Alan Parks, among others, have refined and redirected this model but they all have featured a flawed hero or heroine immersed in routine darkness. 

As an aside, my perfect pub meeting would have been the lock-in when Taggart met Laidlaw. Taggart was the master solver of who dunnit. Laidlaw was tortured by why did he do it and why are we all here anyway? And is that a Grouse? Family-sized? They would, I suspect, have fallen out but what is a Glesca pub for?

But back to Taggart. The cliche is that television detective stories are all about escapism. There are those series about two gardeners of a certain age who stumble upon dirty deeds at the horticultural society and they should be escaped from at the earliest opportunity.

But detective/crime stories attract the best writing and the best television productions because they testify to something we all recognise.

Taggart, certainly, was a brand. But it was also Mark McManus. The road he walked subsequently proved a route for others. In typical Taggart style, Alex Norton’s commandeering of the lead role had followed a previous outing as a murdering butcher. But we believed Norton was still carrying the torch for a wounded human being who was fated to tend to the wounded.

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The personal story of McManus is tragic. He was beset by the loss of those close to him. He was pursued and consumed by the demon drink. These were real-life problems but they followed him from McManus to Taggart.

On screen, his obsession with work led to guilt over his lack of time with a sick wife.

Off screen, he could be found leaning on the bar at Queen’s Park Cafe while trying to salve wounds we can only imagine.

This vulnerability was visible on screen. Taggart was as much a victim as those silhouetted in chalk marks. He was funny. He had to be. He was dealing with the final question: how and why did someone die?

But he was resilient. He had that Glasgow trait of looking death straight in the eye and saying: “Come and have a go if you think you’re hard enough.”

Read more: Will there be a new Taggart series? Blythe Duff on those rumours

This was Taggart. McManus may have been different. But it was surely possible to spot glimpses of those defiant characteristics in his portrayal of the detective.

Death came for him, prematurely and desperately. But the show must go on. Taggart continued.

It still does. Its resonance still sounds a beat in the massed ranks of Tartan Noir. Curiously, Mark Bonnar, a Taggart ingenue, displayed brilliance in Guilt, another Caledonian paean to darkness leavened by extraordinary wit.

It is worth clicking on to STVPlayer merely to hear Maggie Bell, another Glesca great, belting out the theme tune. But it is rewarding to stay as the plot unfolds. There are twists and turns but they matter little. The one, straight road has signposts we all recognise.

It is a story of men and women, flawed and bruised, who attempt to wash away pain, resolve the baffling, comfort the suffering with the imperfect balm of closure. It is about TV deaths. But it was about real life, too, and not just because you identified that spot on Argyll Street where robust remonstrances were proffered when you were a six-year-old heading towards Goldbergs for the school blazer. 

Taggart was a Glasgow story. But it could be told anywhere. That is why there are nods of recognition at the words and actions of its characters from Bargeddie to Bahrain. 

This is why it is important. We are all Jim Taggart’s weans.