Line of Duty viewers have a lot to unpack after this evening's intense episode.

One of the most noteworthy moments - aside from a possible character death - was the unveiling of James Nesbitt as crooked copper Marcus Thurlwell.

This, of course, means he was telling porky pies when he claimed he'd been snubbed from the casting.

The Northern Irish actor previously told reporters: "Even though Line Of Duty had been shot here for years I was never considered for it, which has always slightly galled me."

But his sly misdirect was the from the brain of show pen Jed Mercurio himself.

Line of Duty
His face could be seen on a computer screen

Jed cooked up the fib to throw off fans as James was filming BBC One's Bloodlands near the Line of Duty set.

Now Jed has told: "It was easier to keep it secret by plotting the scheme between the two of us rather than involving a proper casting process.

"I did warn him there were two conditions: One, he'd have to wear shorts which might get very nippy on a cold day in Belfast and, two, he'd have to lie about it.

Line of Duty
Fans were ecstatic to see James join the cast

"The shoot at Belfast Marina went really smoothly, because the sun came out for about five minutes.

"I think people thought Jimmy was shooting an advert. I told passers-by he was modelling for a catalogue.

"The rest of the filming with Jimmy was done away from the public eye so we were able to keep his involvement totally top secret."

James Nesbitt
James and Jed cooked up a lie to trick fans

James, meanwhile, added to The Sun that he's been a fan of Jed's for years - and his work on Bloodlands gave him the perfect opportunity to land a spot on the Line of Duty cast.

He's had to keep his role a secret for upwards of a year - and even kept it under wraps from his friends and family.

Detective Thurlwell was briefly mentioned back in series three, but it wasn't until this evening that we could put a face to a name.

Jed Mercurio
Writer Jed was the genius behind the casting lie

"Love it! James Nesbitt coming our way!" one excited viewer tweeted.

Another just wrote: "Line of Duty James Nesbitt!!!!"

*Line of Duty returns next Sunday at 9pm on BBC One.