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Who is H in Line of Duty? All the clues, theories and suspects so far as the search continues!

Line of Duty
(Image credit: BBC/World Productions)

It's the question every Line of Duty fan is asking... WHO. IS. H? We hope you have mugshots of all the suspects on your wall! And we don't think all the suspects have been found yet!

Who is H in Line of Duty? We hoped the Line of Duty Season 6 would close the plot forever, but it hasn't!

After the pandemic threw production for the sixth series into chaos, we waited an agonising two years to get answers to all those questions Line of Duty Season 5 conjured up - with the most important still being, who is H?

We have put all the clues, theories and suspects together in one place as the search continues!

Lennie James, Craig Parkinson, Neil Morrissey

Dot (centre) revealed huge clues about the identity of H as his dying declaration (Picture: BBC/World Productions/Ed Miller)

What do we know about H so far? 

H is - or we think is - not one but at least four corrupt officers. H is a code name referring to a group of senior ranking corrupt police officers within the Central Police.

The revelation that H was not just one individual but actually a group of officers was revealed by DI Matthew Cottan (Craig Parkinson) as his dying declaration in Line of Duty Season 3.

MORE: Craig Parkinson to host Line of Duty podcast

In the Series 3 finale Dot was fatally injured after being shot three times, however, before he passed away he provided essential information about the group of corrupt officers by blinking when Kate Fleming (Vicky McClure) got to the letter H.

However, it wasn't until Series 5 that Steve Arnott (Martin Compston) noticed that in addition to Dot's blinking he was also making tapping motions with his hands.

In footage recorded on a police bodycam, Dot could be seen using Morse Code to indicate the letter H wasn't necessarily the surname of a person, but a wider group.

In Morse Code, H is four dots, leading the AC-12 gang to conclude that there are four senior ranking members in cahoots with organised crime. However, there appears no logical reason why there can't be more than four corrupt officers. If you're dying and trying to do Morse Code you could make a mistake!

Adrian Dunbar as Hastings and Polly Walker as Gill in Line of Duty

Adrian Dunbar as Hastings and Polly Walker as Gill in Line of Duty (Picture: BBC) (Image credit: BBC/World Productions Ltd)

Who has been identified as part of the H line up? 

So far the names that have been identified are Cottan himself, Derek Hilton and Senior Legal Counsel Gill Biggeloe. In Line of Duty series 6 it was further revealed that Detective Superintendent Ian Buckells was part of this corrupt group. But many fans - including us - can't buy into Buckells masterminding everything. This suggests that a further H is still at large... here we look at the suspects!

Who ele could be H?

Is Superintendent Ted Hastings H? H rating 6/10

Adrian Dunbar as Ted Hastings

Ted might have some secrets, but surely he's not corrupt? (Picture: BBC) (Image credit: BBC/World Productions)

For a time in series 5, it was believed that our beloved Superintendent Ted Hastings (Adrian Dunbar) could in fact be H.

Not only had he started acting suspiciously, but he had also started to take on some of the traits of H (like the now-famous misspelling of 'definitely'), leading to him being questioned about the crimes.

Thankfully Ted was eventually relieved of all charges when it was revealed he'd been set up, with his 'best team' coming to his rescue as they got their hands on some new evidence.

But have all the loose ends been tied up with Hastings? How much do we really know about what Ted gets up to when he's not fighting rogue coppers with AC-12?

In season six, Ted appeared desperate to find out who H is. But is this just covering up the fact he is H? He would be the perfect H in the fact that he's head of anti corruption. He's one of the few suspects that has enough clout within the police it appears to mastermind all these crimes. However, Hastings does seem genuinely distraught that he can't catch H.

Is Chief Constable Philip Osborne H? H rating 7/10

Line of Duty Philip Osborne

Did Osborne order Gail Vella's murder to cover up his crimes?

Now, we don’t like Osborne. But, until recently he just looked like a career obsessed cop. Now, though, we’re starting to think he could be H! He’s certainly in a very powerful position and could be masterminding everything. It was also revealed in series 6 that he was involved in the failed and apparently corrupt investigation of Lawrence Christopher's murder.

With Gail Vella digging into this case, was Osborne involved in her murder behind the scenes? In his role as H did he order that she had to die? Osborne is also getting rid of Hastings. Is this because he thinks Hastings might be onto him?

Is DI Kate Fleming H? H rating 7/10

DI Kate Fleming in Line of Duty

Surely Kate couldn't secretly be H... could she? (Picture: BBC) (Image credit: BBC/World Productions/Steffan Hill)

In a shock twist, fans have been speculating that the one and only Kate Fleming - one of AC-12's finest - could in fact be H.

One reason fans think Kate could be secretly corrupt is based on the fact she is so squeaky clean.

While both Steve Arnott and Ted Hastings have both had some slightly dodgy dealings in the past - Steve with his Lindsay Denton drama in series 2 and 3, and Ted with his financial dodgy dealings - but no one has anything on Kate. Yet.

Over the last few series she has been seen getting home late after work, but where has she been? Working hard to bring down dodgy police officers? Or leaking info to the OCG?

Did Kate shoot dead Ryan Pilkington because he was set to expose her as H?

Is DCC Andrea Wise H? H Rating 8/10

There are three clues pointing to Detective Chief Constable Andrea Wise, played by Elizabeth Rider, being part of H.

The first clue was her determination to remove AC-12 from the investigation into Operation Pear Tree... perhaps because they were getting too close to uncovering the truth?

The second clue is that she was the one to order a separate inquiry into Ted Hastings... was it her plan to frame him for being H?

The third clues is how determined she was to retire Ted in series 6, is that because she's worried he's on to her? But she's not the most exciting character in the world, so we're not sure she's H.

Is DCS Patricia Carmichael H? H Rating 7/10

TV tonight Line of Duty

Hastings’ arch-enemy, DCS Carmichael, is back

Patricia (played by Anna Maxwell Martin) was brought in during Series 5 to investigate Ted Hastings... but her case against him totally fell apart at the last hurdle.

However some fans are convinced that her determination to put the spotlight on Ted was a way of covering her own shady dealings with organised crime. The character made a comeback in season 6. It looks like she’s taking over anti-corruption as Ted exits - wouldn’t it be ironic if she was H?!

There’s a theory that Jimmy Lakewell told Steve Carmichael was H in episode four of series 6. Lakewell told Steve that he needs to “Look beyond the race claim to find H.”

Now, “race claim” is an anagram of Carmichael except for the letter H! So it must be Carmichael!? Erm, even in the crazy world of Line of Duty this seems rather unlikely!

Assuming there is a seventh series, Carmichael looks set to still have a big part to play.

Marcus Thurwell - H Rating 5/10

Marcus Thurwell Line of Duty

Marcus Thurwell

Rather excitingly in episode 5 if series 6 it was revealed that James Nesbitt was playing dodgy retired cop Marcus Thurwell. Now, the fact that Nesbitt has been cast is a clue in itself. Why cast such a well-known actor if he’s not going to play a significant role?

We know that Thurwell was the Senior Investigating Officer on the death of Lawrence Christopher, who died in police custody. It’s been revealed that Gail Vella was looking into this case.

Thurwell was also involved in another case, a murder organised by the OCG, which had links to the Sands View Boys Home sexual abuse scandal.

But while Thurwell is clearly likely to be corrupt, he was also apparently found dead at his Spanish home at the end of episode 5 of season 6.

Fans have got a theory that Thurwell has simply faked his own death after being tipped off that AC-12 were on to him. I could be likely... so could this mean we get to see Thurwell face questioning in the interrogation room after all?

Could Thurwell return from the dead in series 7?

You can catch up on series 1-6 on BBC iPlayer