What Line of Duty and Game of Thrones have in common: both their finales were a total anticlimax

For fans of convoluted, self-mythologising television filmed in Belfast, the underwhelming Line of Duty finale will have brought a crushing sense of déjà vu. We’ve been here before only with Mother of Dragons rather than Mother of God references. And with Jon Snow mooching into the great beyond instead of Kate and Steve heading to the pub.

Jed Mercurio, a feisty sort who loves a challenge and has proved willing to deploy a four letter c-word that isn’t “CHIS” when tackling critics, has outdone himself. He’s produced a season closer that echoes, occasionally beat-for-beat, the rise and fall of Game of Thrones. AC-12, it turns out, is the new Westeros. And in the end, Ted Hastings v H was revealed to be every bit as massive a waste of time as Jon Snow against the White Walkers.

It might even be worse than that. Although the BBC is said to be in talks with Mercurio, a seventh season of Line of Duty has yet to be confirmed. And there was a distinct ring of finality as the end credits rolled on series six, with Ted and co squeezed into that weirdly-proportioned lift (which looked a bit like the one Jon Snow used to take to the top of Wall). So it could be that we’ve just said ta-ra to Ted. Which would make this soggy sausage of a final instalment.

Both Game of Thrones and Line of Duty burst out of the traps with shocking first seasons that ripped up the rule book. Displaying nerves of gleaming steel, and with an infectious derring-do, they bravely killed off big-name characters. On GoT, it was Sean Bean’s Ned Stark. With LoD it was Lennie James’s Tony Gates. In each case the showrunners were making a declaration. Tropes were for twerps. Nothing was off the table.

In the end, alas, each came down with a terminal case of pulling their punches. Game of Thrones had built its reputation around its enthusiasm for bumping off our favourite heroes and villains. And yet by season eight Jon, Bran, Daenerys and Tyrion etc were all far too beloved to be dispatched before the final curtain.

Mercurio ultimately fell victim to the same compulsion to play it safe. He gave us an almighty stand off (not unlike the battle with the white walkers at Winterfell...) when Ryan Pilkington and Kate Fleming had a shoot out in episode five, yet balked at the truly shocking death that moment required: Fleming's herself.

And had he truly wished to subvert expectations he would have gone with what may well have been his first instinct and confirmed Ted Hastings as mega-villain “H” all along.

That, though, would have jeopardised the Line of Duty brand – people would genuinely have been appalled. Forget sucking diesel, we’d have all been spewing up our tea. So he revealed H to be played-for-chuckles B-lister DS Ian Buckells. It was a cop-out as spectacular as having the Night King killed by… Arya Stark. Because who saw that coming, right?

Even at a structural level, Line of Duty and Game of Thrones took their bows in similar fashion. The final episode of Game of Thrones started with a clamorous set piece in which Jon kills Daenerys and Drogon became upset.

And then it devolved into a snoozy chat-fest as the surviving characters decided who should be king. Line of Duty traced the same arc, with an action-packed sequence in which Steve and Kate rescued Jo Davidson from an OCG hit-squad giving way to endless chin-wagging back at police HQ.

Line of Duty also echoed late-stage Game of Thrones in painting characters into impossible corners and then, with a finger click, making the problem go away. Remember when Jon Snow and his merry men were surrounded by White Walkers only for Daenerys to make a hyperspace jump to their rescue? She had done so by crossing half the continent of Westeros in a few hours on the back of a dragon which could apparently break the sound barrier – all without ruffling her statement braids.

Mercurio must have been taking notes, as he used precisely the same hand-waving to shrug aside Steve Arnott’s prescription drug use: a storyline that carried no consequences beyond saddling Steve with a banana-hued taser. Logic had already gone sailing out the window when Kate Fleming killed Ryan Pilkington – and then went on the run, Thelma-and-Louise style with Kelly Macdonald’s Jo Davidson.

They were on the same side as their pursuers – so why the flight from justice? Presumably because Mercurio thought it would be terribly cool to have Kate and Jo star in their own mini road movie. It was a huge, honking contrivance that served only to break the spell, much as Game of Thrones had over and over as its steered into its endgame.

The two shows also suffered a weird shrinking effect. The more popular they grew the smaller their worlds seemed. Game of Thrones started as a rich fantasy teeming with characters. By the end it felt as if all of six people lived in Westeros. Similarly the first season of Line of Duty was a ripped -from-the-headlines thriller that interrogated issues such as extrajudicial police killings and the toxic effect of corruption on big institutions.

Yet in the end it would become as tiny and airless as Game of Thrones. Everyone was either a bent copper, a straight copper who was potentially a bent copper, or a bent copper living in Spain and actually dead all along (take a bow James Nesbitt, aka Marcus Thurwell, aka the H that was Promised).

If anything Line of Duty ultimately was further removed from the real world than Game of Thrones. Yes, GoT had dragons and Kit Harington walking around with a dead wolf around his shoulders. But Line of Duty’s CHIS-whiz lingo was more convoluted than High Valyrian. And the return to the Seven Kingdoms of Beric Dondarrion and Gendry Baratheon were as nothing compared to all the obscure characters Mercurio insisted on recycling.

He did so to the point where it became impossible to watch Line of Duty without referring constantly to its Wikipedia page. The series was high, to the level of incoherence, on its own mythology – a pitfall even Game of Thrones generally avoided.

Tonally, too, Thrones and Duty were in lockstep. Remember how underwhelmed we all felt when Game of Throne ended with Jon Snow returning to the Night’s Watch and marching beyond the Wall?

The very same anticlimax struck as we saw Jo Davidson sign up to the LoD equivalent of Taking the Black: “immunity from prosecution and witness protection”. Davidson looked at peace as she ambled into the figurative sunset. Viewers already burnt once by Game of Thrones will wonder how they let themselves be suckered a second time – and in precisely the same fashion.