I DID my homework conscientiously for the first programme in Line of Duty, series 6. I’d been following this police drama since it started in 2012, and series 1 to 5 have been re-watched twice.

Naturally, Adrian Dunbar, Vicky McLure, and Martin Compston were etched into my brain, never to be forgotten, but from Lennie James and Keeley Hawes to Thandie Newton and Stephen Graham, I also knew the larger cast of characters by name, even all the shifty chief constables.

So when mention of Jackie Laverty and Ryan Pilkington resurfaced in this latest Series 6, I wasn’t flummoxed.

Unlike those who complained that it required too much prior knowledge, I understood the significance of that golf iron in DS Buckells’ hand. But when Series 6 kicked off with a “chis handler” reporting “intel graded A1 on the matrix”, it became obvious that coasting wasn’t going to be an option. This learning curve was going to be steep.

To keep up and get the maximum out of series 6, I now watch each programme twice. No hardship there.

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And further pleasurable preparation continues by tuning in to the Obsessed with Line of Duty podcast on BBC Sounds, where actor Craig Parkinson, better known to the series’ devotees as DI Matthew "Dot" Cottan, or The Caddy, chews over the latest episode with a guest, and speculates on evolving plot lines.

If I undertook a PHD, I doubt I’d approach my subject so assiduously.

What I treasure about Line of Duty is that it exercises your your brain and tests your memory. What a tonic! Most TV is a repeat, or derivatively formulaic, and about as intellectually stimulating as Styrofoam, designed to be consumed passively for its sedative effects.

With Covid restrictions – no concerts, theatre, ballet, opera, cinema – our cultural life has been brutally curtailed. Before lockdown you could afford to ignore 99% of TV programming because you could escape to the cinema, and even challenge yourself by watching a film with subtitles.

The last film I saw before cinema doors closed was Parasite, from the South Korean director Bong Joon-ho. Now there’s a film that makes you think, one that lends itself to analysis, a film that would repay a second viewing. I live in hope that we’ll get a chance to see the newish black and white version when cinemas reopen.

Bong Joon-ho sees black and white as a way to make Parasite a cinema classic for posterity. "I think it may be vanity on my part, but when I think of the classics, they're all in black and white.”

But some critics see that as a snob marketing gambit to generate repeat box-office business. A similarly scathing school of thought dismisses the more active level of participation required by Line of Duty series 6 as a self-indulgent exercise in acronyms and past references that are incomprehensible to new viewers.

Is such resistance another sign of our growing national attention deficit disorder, where all information, communication and entertainment has to be served up in bite-sized doses?

Social media certainly grooms our short attention span. When Twitter doubled its Tweet character limit from 140 characters to 280 characters in 2017, one suspects that this was too much cerebral overload for some.

Social media cultivates the attention span of a flea. If a thought can’t be consumed and digested in the blinking of an eye, it trains us to lose patience. This is one reason why nuanced arguments increasingly struggle for air space in the bald and shouty public discourse.

And this creeping attention deficit disease is horribly contagious.

We’ll scroll through any reading material that comes our way, searching out the executive summary. When we're weighing up whether to read something or not, those now common little nudges, which reassure us that it’s only going to be a five- or eight-minute read, are clinchers. Longer documents just beg to be left sitting in the inbox, awaiting oblivion.

This is not a trend that bodes well for the nation’s intellectual life. It makes us pushovers for accepting all the facile, mind-bending propaganda that comes our way.

Government Covid fear adverts are a prime example. Arresting, emotive, they tell us what to believe and how to react. That’s the opposite of critical thinking.

Some of the best advice I ever got was from an English teacher who taught us to persevere with ‘difficult’ novels even though we didn’t understand every element as we read along.

“Don’t worry about the detail or the odd word you don’t understand, just keep going, get the gist, and you’ll get it in the end” she told us. And if we remained perplexed, we’d discuss it in class, which was often revelatory.

Of course, some cultural offerings are initially daunting. I remember being ever so grateful for the genealogical table at the beginning of Wuthering Heights. Russian classic literature was confusing and frustrating without that opening list of dramatis personae, a code for decrypting those three-part names.

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Hilary Mantel’s Wolf Hall was another uphill struggle. It forced me to refer back constantly to the cast of characters and the family trees in the book’s opening pages, by category – clergy, ambassadors, Yorkists, Seymours – and by location – Calais, Hatfield, Court, Chelsea.

Even then, there were times when I wasn’t sure who, exactly, was speaking. But in the end, Mantel’s novel rewarded the effort.

Without a willingness to travel a demanding cultural road hopefully in the expectation of getting enlightenment at the end of it, we all become that bit stupider.

Apply control freakery to culture, that lazy, insecure need to comprehend ever twist and turn instantly, and you end up watching the asinine MasterChef, presented by “yer wee fellas” Gregg Wallace and John Torode.

Its script and characters might as well be written by an artificial intelligence algorithm, so you’ll have no problem keeping up.

As Ted Hastings would say, God give me strength.