Line of Duty creator Jed Mercurio has admitted that James Nesbitt's much-discussed cameo in the show was a deliberate attempt to misdirect viewers.

Warning: Spoilers ahead for season six of Line of Duty.

The Northern Irish star appeared as former police office Marcus Thurwell in the sixth season of the hit police drama, but only actually featured in photographs.

Many fans speculated that Thurwell could have been "the fourth man", otherwise known as "H" after his name cropped up in relation to historical police investigations.

However, his character was confirmed to be dead in the penultimate episode of the series, before Nesbitt had even appeared on screen in the role.

In an interview with Den of Geek, Mecurio revealed that he hired the famous actor to pose in the images as a deliberate way to throw viewers off the scent.

He said: "The first conversation I had with Jimmy is 'The whole point of this is you have to lie through your teeth and misdirect'.

"We thought if that picture is just someone who’s a random guy in Belfast, then the audience isn’t going to get as invested as they would be if it’s a big star. They’ll think, well of course that means that he’s H and he’s going to arrive all guns blazing."

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Mercurio continued: "Again, it was another misdirect, built around the fact that the intention with season six was that it would be about mystery more than about the jeopardy.

"The audience's investment was in the H enigma and not knowing who it was, rather like a closed circle mystery, a country house detective story, revealing who the person is in a way that was most surprising and I would argue most unexpected and subversive."

"H" was eventually revealed to be Ian Buckells in the series six finale, which proved to be divisive among fans.

Meanwhile, actor Owen Teale, who played the clearly dodgy Chief Constable Philip Osborne in the show, told us he would "love" to return for a potential seventh series.

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