Lately, among newspaper columnists and keyboard jockeys in the Fourth Estate gallop, there’s a tendency to shoehorn in a mention of a popular show that they’re also totes into too, honest, in an attempt to let you know they’re relevant.

Popular namedrops include True Detective, Borgen, House of Cards and, yes, they’re good shows. But the weird thing is that no one mentions Line of Duty, which is just as good, if not better. Because it’s not only British original drama; it’s the most exciting thing to happen to a Wednesday night since the invention of the capital ‘W’.

And even if the adrenal heartbeat of Line of Duty slows slightly this week, it’s so that it can allow the viewer to collate the many thrashing plot strands. The most interesting one of which is who Jane Akers was taking bribes from. Turns out it’s a familiar face (if you saw the first series).

We mentioned DI Cottan’s connection to Series 1’s gangster Tommy last week, little knowing that the angry Scot himself would show up. But there he is, shouting down the screen like a man on the wrong side of a pub lock-in. No wonder Cottan (surely ‘The Caddy’) has the appearance of a man who just accidentally swallowed a live pigeon.

It’s such an unexpected knitting together Series 1 and 2 that you’d be forgiven for momentarily forgetting DCC Dryden (Mark Bonnar) is still under the interrogation for ‘Huhne-ing’ (topical!..ish) his way out of points for speeding, and getting increasingly feisty as he’s cornered in another classic interview scene.

If Line of Duty made a whole hour out of an interview it’d likely be the best thing on TV this year.

Meanwhile Dryden’s ex-lover Denton, aka ‘Prisoner 24601’, visits her stroke-afflicted mother in a scene that I can’t recall because all my notes were smudged by tears. It really was an affecting bit of bedside drama – all meaningful stares and unsaid sentences – with Keeley Hawes being so painfully terrific in being so terrifically pained that she may as well have started weeping award nominations as she lied to her dying mum.

And just as it looks like Denton’s day has gone from bad to worse, it goes to worser…er. Her prison van is rammed off the road, her guards killed, and she is kidnapped by two officers involved in the disappearance of Denton’s missing person’s case, Carly. One of them is An Adventure in Space and Time’s Sacha Dhawan, who’s always a welcome face on TV, even if he’s being scary-face here. And as much as another piece of the puzzle is revealed by his presence, the real question is where that piece fits.

How are the murder of a witness and the disappearance of a girl linked? And is Denton’s affair with Dryden a relevant piece of the jigsaw? Who knows. This is the kind of brainteaser the Beeb should be exporting right now so that foreign columnists can shoehorn it into their articles. Until that happens we in Blighty have the pleasure to keep calm and carry on watching. House of Cards can wait.

Aired at 9pm on Wednesday 5 March 2014 on BBC Two.

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