When Line of Duty first aired in 2012, it was an under-the-radar show that nonetheless delivered excellent ratings for BBC2, to say nothing of superlative reviews. Its pleasures were obvious from the outset: superb performances from an excellent cast that included the great Adrian Dunbar as Superintendent Hastings (“like the battle”), the all-knowing head of AC-12, the anti-corruption department within the police force. The dialogue seemed to be littered with authentic-sounding acronyms such as OCG and UCO, and the show had a cleverly paced, twisty storyline that spiced up what may have been a relatively straightforward police procedural with long, brilliantly scripted interrogation scenes that owed as much to playwrights such as Pinter as they did to contemporary television drama.

As it has returned for its sixth series, much has changed. It is now a phenomenon, the most popular TV drama of its generation, and its leading actors, Dunbar, Martin Compston and the ever-superb Vicky McClure, have become household names. And its creator Jed Mercurio has become synonymous, thanks to this and Bodyguard, with high-impact, twist-laden crime shows that gain much of their power from the show not being available to binge in one go on iPlayer, but instead being parcelled out week by week, with a nation on the edge of their seats waiting to find out what is going on.

The first two episodes have had a slower feel at odds with the fast-paced brilliance of earlier storylines

Unfortunately, the issue this time has been disappointment and disillusionment, rather than previous series’ elegant and exciting opening salvoes. Before now, guest stars of the calibre of Daniel Mays, Jason Watkins and Jessica Raine were unceremoniously dispatched by the end of the first episode, leading the audience to believe that any character could be dispensable. There was none of the usual certainty of these programmes that the big-name actors would last until the end. But now, perhaps as a result of the show’s much-publicised hiatus due to Covid restrictions, the first two episodes have had a curiously pedestrian quality distinctly at odds with the fast-paced brilliance of earlier storylines.

A large part of this is that Line of Duty now seems mired in the complexity of its own, arguably over-elaborate backstory, much of it revolving around the identity of the mysterious “H”, supposedly the crime lord whose actions have dictated most of the goings-on that AC-12 have been entangled in. The presence of the brilliant Kelly MacDonald as the new antagonist is a very welcome one, but unless you have an encyclopaedic recollection for exactly which actor played which role in earlier series, you are likely to spend each episode as baffled as you are enthralled. Little wonder that countless blogs and news articles spring into life at the end of each instalment, attempting to explain to the uninitiated exactly what on earth is going on.

In this regard, Line of Duty mirrors many recent dramas in both TV and film, with the regrettable rise of “the new incomprehensibility”. Christopher Nolan’s latest blockbuster Tenet was widely trumpeted as “the destroyer of Covid fear” when it came to audiences returning to the cinemas last year, but it became his least financially successful project since 2006’s The Prestige. This was partly because it simply couldn’t make its money back without the world’s film emporia being open, but also because most people who braved potential infection to visit their local cinema were utterly bewildered by the over-complicated, poorly explained storyline. Little wonder that Nolan, for so long the untouchable crown prince of cinema, has now lost some of his lustre, most recently receiving the questionable accolade of being guyed by Michael Spencer, everyone’s favourite comedic innovator.

There have been many other examples of these over-stuffed, over-complicated dramas recently, especially with long-running film and television sagas that seem to mistake incoherent plotting for dramatic interest. When the final season of Game of Thrones ground to its fiery and murderous end, it left many viewers dissatisfied despite concluding with a much-anticipated orgy of destruction and death, all covered in state-of-the-art special effects. Complex and intricate plot developments — in some cases carefully foreshadowed from the first series onwards — were dealt with in a rushed and unsatisfactory fashion, meaning that would-be seismic revelations carried all the emotional weight of an episode of Last of the Summer Wine.

Unclear storytelling means that an audience who want to be entertained end up being frustrated

These tendencies to portentous grandiosity are, of course, not a recent phenomenon. The show Lost notoriously developed its strange mythology — polar bears on Pacific islands, and what-have-you — over six seasons, only to end in an incomprehensible cop-out that outraged its admirers. Yet it had created its own problems from an early stage; it collapsed under the weight of its own allusions and hints at greater truths, and so, perhaps appropriately, the journey proved to be a great deal more interesting than the destination. A similar problem has beset everything from the Pirates of the Caribbean films to the Harry Potter books and subsequent cinematic adaptations (to say nothing of the Fantastic Beasts spin-off series). The quality of the storytelling is muddled, confused and desperately unclear, meaning that an audience who want to be entertained end up being frustrated, even angered, instead.

This remains an enduring problem in both film and television. Over and over again, there is an instinct on the part of writers, producers and directors to give unearned grandiosity to a straightforward narrative and thereby transform it into that most twenty-first century of things, “An Epic”. This has meant that the average running time of films has long since crept past the two hour mark (even the new James Bond film, No Time To Die, is said to run nearly three hours, suggesting it should be renamed “Plenty Of Time In The Cinema”), but the films cannot be made shorter, as otherwise they would be incomprehensible.

Perhaps Jed Mercurio, Christopher Nolan and their ilk might be better off moving away from the increasingly bloated mythologies and epics that they are in thrall to and returning to the smaller, character-based drama in which they began their careers. They would do well to remember Alfred Hitchcock’s pained dictum: “One of the fatal things in all suspense is to have a mind that is confused. Otherwise the audience won’t emote.”