Viewer watching Sunday's Line of Duty were left reeling by a spelling error which fuelled speculation on who the always mysterious H might be.
After a huge audience tuned into last Sundays episode, which brought a shock death and THAT cliffhanger involving Jo Davidson's blood relative, millions tuned into BBC1 for the fifth episode of series 6.
And, after the bombshell on Jo's DNA link was left out of the bag, fans were left wishing they'd taken a leaf out of Jenny from Gogglebox's book and invested in a notepad as more twists unfolded.
One of the biggest bug bears of devotees of all things AC-12 is the identity o just who H might be, but some believe they might be a step closer to uncovering their identity by way of a spelling error that reemerged from past series.
The mis-spelling of definitely as 'defiinately' in a message aroused many suspicions once again, with one viewer reacting: "That misspelling of 'Definately' must be a clue" and another tweeting: "The bets they'll catch h in person just by the Definately spelling mistake somewhere."
A third posted: "Whoever is on the pc talking to Jo, HE/SHE SPELT DEFINATELY WRONG, LIKE THEY SPELT IT WRONG WHEN JOHN CORBETT WAS TRYING TO SET UP THE EASTFIELD DEPOT. SPELT EXACTLY THE SAME" and another exclaimed: "Someone DEFINATELY just caused our eyebrows to shoot up so high that they disappeared into our hairline"
By the end of Sunday's Line of Duty, there was a much bigger talking point when both Kate and the shady as ever Ryan Pilkington pointed the trigger at each other as Jo looked on, with shots sounding out just as the credits rolled.
That left a captive audience wondering just what they'd be tuning into when next Sunday's penultimate episode of the current series airs.