Many are still recovering from the Line of Duty finale that revealed a major moment that had been almost ten years in the making.
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Ian Buckells was exposed as the elusive fourth man in a ring of corrupt police officers, otherwise known as 'H' – but it seems that Line of Duty's creator Jed Mercurio had planned for Buckells to be a bent copper since the beginning.
The writer revealed that he dropped a major clue way back in the first series, which was released in 2011, that pointed to Ian being involved in corrupt police work.
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Speaking to former star of the show, Craig Parkinson, who plays Matthew 'Dot' Cottan, on his podcast Obsessed with Line of Duty, Jed explained further about the specific moment.
"It was really about the heritage of the series, going all the way back to season one, where Dot Cottan says, 'Oh, can I just have a quick word with Tommy Hunter in the back of the van?' and Buckells goes, 'Yeah, alright'. OK, like, really, is that what you should be doing? Of course, not."
Jed also explained: "It was always really important to me that it was someone who had been in season one, someone who had been there the whole time.
"We did introduce some characters late, so Thurwell came in late, we went back to Fairbank, who’d appeared in season three, we had the Chief Constable, who had obviously been there since season one."
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© Photo: BBCWhat did you think of the finale?
Despite Buckells, who officially became H after Tommy Hunter's murder, knowing far more regarding the institutionalised corruption in the police force, his "bumbling idiot" persona hoodwinked many.
It was this attitude that made it "unrealistic" for him to be the fourth man in some viewers' opinion, while others praised Jed's effort to pin H on someone from the original cast.
The mixed reaction from fans on the final episode of series six didn't go unnoticed by the show's cast. Martin Compston, who plays DI Steven Arnott, admitted he "fully understood" why some weren't completely satisfied.
After the finale aired, he said on social media: "We've truly been blown away by the reaction and love for the show, we're proud of it. Fully understand it wasn't the 'urgent exit' type ending some anticipated but we appreciate you sticking with us."
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