Line of Duty fans have a new theory on who H is after doing some investigative work of their own following Sunday night's show which saw the return of Patricia Carmichael, played by Anna Maxwell Martin. Warning, potential spoilers ahead for season six!
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The Detective Chief Superintendent who heads up AC-3 appeared towards the end of the episode and didn't waste any time in throwing AC-12's investigation into the cover-up of Gail Vella's murder into mayhem.
Now some fans have spotted that way back on Sunday 14 March a week before series six premiered, the actress posted what seemed like a pretty innocuous photo that not only teased her return but perhaps a bigger clue about her real identity.
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Alongside a photo of her adorable dog Bobby sitting beside her on the sofa, she wrote: "Definately mama to this bank drain".
At the time of posting, viewers weren't aware that the 43-year-old actress would be reprising her role on the show so didn't take much notice. But now social media has come alive with the theory that Carmichael is going to be exposed as H before the series is over.
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"Lovely photo but look at the spelling of 'definitely' could she be H?" one follower commented underneath the snap. A second echoed: "Note the misspelling of definitely," while a third simply wrote: "H!!!!!!"
Over on Twitter, another user weighed in: "Did Anna Maxwell-Martin 'definately' make a genuine spelling mistake or is this a cleverly hidden clue regarding Patricia Carmichael?! (Or maybe it's her cute dog that's corrupt)."
Anna first appeared as Patricia Carmichael in season five
As we know, the misspelling of definitely as "definately" is a trademark of the elusive H. The typo first popped up in series five when John Corbett (Stephen Graham) was exchanging messages with the secret criminal mastermind and happened again in the most recent episode when Jo Davidson logged on to tell them she wanted out of their shady dealings.
After being told that she needed to lure DCI Kate Fleming (Vicky McClure) into a trap so that Ryan could dispose of her, Jo responded that she'll only do it "As long as it's my last job," to which H responded: "Definately".
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Meanwhile, another theory that points to Carmichael being H has been gaining traction on Reddit and Twitter - and we think coupled together with Anna's own clue fans could be on to something here!
Back in episode four, Jimmy Lakewell refused to speak to DS Steve Arnott (Martin Compston) about what Gail Vella had been looking into but cryptically told him: "Look beyond the race claim to find H".
Jimmy Lakewell gave Steve a cryptic answer when asked about the investigation
As some super sleuths have worked out, if you were to take the letters from "race claim" from her surname, the only letter that is left is H. "We all know Patricia Carmichael is H. Jimmy Lakewell said 'look beyond the race claim to find H'," tweeted one viewer. "So take the letters of RACE CLAIM from the letters of CARMICHAEL. What do you get? H. Solved it."
Someone else added: "RACE CLAIM + H is an anagram of CARMICHAEL. My head has just exploded."
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