So 8pm on Sunday night and in an hour, I will be tuning into Line of Duty (season 6 episode 6). The writing, the acting and the drama itself are brilliant. And the fact that five of the six series have used Belfast as a location helps.

Maybe it is a feature of LockDown giving us all a sense of virtual community. But the cliffhangers and the Twitter feeds speculating what happens next week gives it all a sense of occasion.

But it all covers up a plot that is too unrealistic that suspension of belief is more required than in any drama I can remember.

There have been six series of six or seven episodes beginning in 2010.

The plot is an ongoing battle between AC12 (the Anti Corruption unit) at the fictional Central Police …the first series was made on location in Birmingham….and an OCG (Organised Criminal Gang) which has infiltrated the police.

Personally I find it difficult to think that so many senior police officers do not seem to know each other and that a police service this corrupt would not be disbanded. The number of police officers good and bad, killed in six series is a multiple of how many police officers have actually been killed…in the line of duty.

The theme is that the each season, the finale leads to more questions and so the next season has a link to the past season. A character, half forgotten from series 2 shows up in series 5 and so on. So a viewer needs to be attentive.

The three good guys or seemingly good guys are Supt Hastings (Adrian Dunbar), DI Kate Fleming (Vicky McClure), DI Steve Arnott (Martin Compson). Hastings and Arnott have both come under suspicion as being a mole for the OCG.

But it is Supt Ted Hastings “like the battle” who is most enigmatic.

In part, there are two story-lines. One seems like criminal activity in the midlands of England and the other that runs alongside is related to Ted’s past in the Royal Ulster Constabulary.

That is Edward Gerard Hastings, who was born to a Protestant father and Catholic mother and who joined the RUC. As he said in series one, this was unusual for a Catholic. Memorably he claimed he was injured in a bomb explosion…in which a fellow Catholic officer was killed…..seemingly set up by a fellow officer.

In series five it emerged that Ted had a Catholic lover who fed him information from the IRA and she was subsequently killed as a “tout”. He moved to England.

In private conversation with a suspect…a retired senior officer and later convicted of child abuse, Arnott notices that Ted shakes hands with the suspect. It is a masonic handshake, unusual for a Catholic. But is Ted merely using it to gain trust?

The officer who cost Hastings his savings and his marriage and who attempted to bribe him is ex-RUC.

In this (sixth and probably final) series, there are hints at corruption in broader society. When Ted angrily denounces the new Chief Constable “we appoint proven liars to highest positions”, is he referencing Boris Johnson? The death in custody (years before the first series) of black student “Christopher Stephens” is a reference to the institutionalised racism in the cases of Stephen Lawrence and Christopher Adler.

And surely the doctored photographs of fictional police paedophiles with Jimmy Savile is a nod in the direction of VIP paedophile rings. And maybe the fictional “Sands” Childrens Home is a reference to Belfast’s very own Kincora.

To some extent, the “Ted-isms”…….Hastings used Belfast phrases. “I didnt come up the Lagan in a bubble”, “sucking diesel”, “cooking with gas” underscores the Norn Iron dimension to all of this.

As Ted himself might say, he is “the big lad in the big picture”.

Of course all Line of Duty fans have theories as it is believed Jed Mercurio plants little nuggets. The main OCG man the unseen, undiscovered “H” is it Hastings, is there a clue in the pattern of the kitchen tiles in Steph Corbetts house in Liverpool ….or is there a clue in “dont believe the race claim”…….as “race claim” is a near anagram of “Carmichael” without the H….a police character.

But last weeks episode (oops it is 8.58pm…lucky I am recording the programme) provided evidence of the Norn Iron link. Ted looks at a photograph of a group of RUC sergeants. Is the man who set Ted up one of them?

And a retired Central police detective living in Spain ….we saw his photograph last week will be played by our own, our very own Jimmy Nesbitt.

So is “H” the OCG chief an ex RUC man.

Surely not. I hope the DUP ask questions in the House of Commons and write to the BBC.

On a personal note, I have a lot of time for Adrian Dunbar. He wrote a movie “Hear My Song” some twenty five years ago, in which my fathers cousin, A Dublin-based actor had a part. And I saw him at the Fermanagh-Armagh GAA Ulster Final about ten years ago.

But Irish actors……their success, Dunbar, Nesbitt, Liam Neeson, Stephen Rea and southerners like Colm Meaney, Gabriel Byrne…………in a way they are following a path that older actors, J G Devlin, Lily Begley, Joe Tomelty, Harry Towb……….David Kelly, Noel Purcell and many others made for them.

In the 1950s and 1960s Irish actors were confined to “Oirish parts” …my father knew Jimmy Devlin and Lily Begley……….and ultimately it was The Troubles that gave young Irish actors to play the routine “gunman” type parts and led to better things.

I hope I am right. I hope it was the RUC. Or the Freemasons.