Who is H in Line of Duty? Fans are convinced they’ve figured out the real culprit

AS the finale is just around the corner, BBC One’s Line of Duty has teased one of the biggest mysteries in television history.

And fans are desperately trying to figure out who H is. And could this new theory lead us any closer to the answer? Find out below…

Who is H?

We have lined up the suspects that could be the evil H.

Take a look at our rundown here...

Ted Hastings

It would quite honestly be too obvious for H to be Ted Hastings - and fans seem to agree.

One viewer said: "No way is H Hastings - too obvious! I bet whoever is running the OCG doesn't even have a name beginning with 'H' - that's a disguise & to frame Hastings!....something not right about Gill at all!!"

During episode five on April 28, Ted is arrested on two charges - corruption and conspiracy to murder.

Ted poses as H in an undercover operation, which he stresses is the only way to take down the OCG and recover the stolen Eastfield Depot bounty.

As his behaviour becomes irrational, DI Kate Fleming and Steve Arnott report their gaffer to Deputy Chief Constable Andrea Wise.

Ted tries to explain that he’s being framed as the suspicious envelope of £50,000 from Mark Moffat is found in his hotel room and Fleming and Arnott find Northern Ireland links to John Corbett.

Patricia Carmichael

She’s ruffled some feathers with viewers for her unlikeable approach during the process of interviewing Ted Hastings regarding his charges.

But could AC-3 boss DCS Patricia Carmichael be smart enough to hatch a plan that could see Ted get locked up for a crime he didn't commit?

Carmichael has stressed that she’ll prove Ted is guilty, which viewers feel is her way of saying she’s going to frame Hastings.

While actress Anna Maxwell Martin, who portrays the character, only has a recurring guest spot on the show, fans are convinced she could very well return as a lead actor for season six if she is H all along.

Derek Hilton

As series five begins it's believed that H has been unmasked as DCC Derek Hilton - who was killed at the end of series four.

But it is soon obvious that H is still active, so the likelihood of Hilton being the culprit is waning.

Derek was implicated by his initial and as a senior ranking officer who had suggested that corrupt cop Dot Cottan receives a promotion.

Cottan had shared a personal relationship with the character since the first series.

Hilton was seen making a call to have Arnott killed by a balaclava man.

Les Hargreaves

It’s not hard to see why Les Hargreaves would fit the description of H rather well.

Again, his surname begins with the letter H and he famously held a senior position in the police force, meaning that he had authority over others.

He’s never been a fan of AC-12, so it would make sense that he would frame Ted in a way that could see him locked up for good.

He's obviously a bent copper, having been killed wearing a balaclava at the Eastfields depot raid.

Certain remarks made by Lisa McQueen seemed to hint that Hargreaves was just another cop who’d been hired from the OCG but, oddly enough, he didn’t even know where the headquarters were located.

She said: “We never told Hargreaves about the print shop, the leak came from somewhere else.”

Gill Biggeloe

It goes without saying that Gill’s behaviour throughout the fifth series has been suspicious, to say the least.

Viewers know that Gill has feelings towards Hastings, but it seems that his loyalty to being a dedicated family man is bothersome to someone like Gill.

She asked him to retire from his job in fear of ruining his reputation, but then changes her tune and shows major support for Ted when she vouches for his talents in front of DCC Wise.

Later on, Gill, after having offered her legal services, hands Ted a Regulation 15 notice that would suspend him from his duties.

Her behaviour has been all over the place, and fans have a theory that Cottan blinked G not H on his deathbed.