Line of Duty fans get an answer on 'H' clue in last nights episode after 'aggressive' Phil interrogates DCS Carmichael

Phillip Schofield was called 'aggressive' as he turned into a Line of Duty superfan to 'interrogate' Anna Maxwell Martin on This Morning, after claiming she sent morse code during a key scene in last night's show.

The penultimate episode saw Kelly MacDonald's character Jo Davidson being grilled by Martin's character, DCS Patricia Carmichael, for a scene that lasted nearly half an hour of the episode.

In the scene, which sent hardcore Line of Duty fans into meltdown on Twitter during the show, Martin taps her pen four times after an evasive Jo Davidson avoids her questions.

However, Phil and thousands of other followers of the show noticed that the four taps translate into 'H' in morse code.

Philip Schofield questions Anna Maxwell Martin on whether she sent 'H' in morse code as a clue during penultimate episode of Line of Duty (This Morning | ITV)

Phil said to a giggly Anna: "Don't claim to me like you don't remember this moment!"

Anna burst into laughter saying: "Phil! That's very aggressive!"

Both laughing, Phil added: "So, you're in the interview room and you tap the pen four times, let's have a look at this moment."

Before the screen cut away to a snippet of last night's show, a seemingly clueless Anna looked stunned before laughing and holding her head in her hand.

After the clip, Phil added: "That's H! That's H in morse code!", but her reply left both Phil and Holly clueless.

Still laughing, Anna protested: "I didn't know that! I didn't know that, I think I was just bored!

"You know, those scenes are very long and I think I was just like 'What, am I, saying, next' erm..."

"Yeah, yeah, yeah!", interjected Phil before Holly said: "I mean you are such a brilliant actress that you could be just pulling the wool over our eyes completely here, Anna, and I think that may be what's happening."

Earlier in the day, Kelly MacDonald spoke to BBC Breakfast about the latest twists and turns in the series and gave a 'no comment' interview in the exact style which infuriated DCS Carmichael during last night's show.

The actress, who plays DCI Joanne Davidson, was appearing on Breakfast TV after the dramatic penultimate episode of the Jed Mercurio crime drama.

And BBC Breakfast's Dan Walker tried to do the nation a favour and answer some of the many questions ahead of the finale next Sunday - but his AC-12 interview skills probably need a brush-up, as all he got was no comment.

Line of Duty concludes at 9pm on Sunday, May 2 on BBC One.

This Morning returns weekdays from 10am on ITV.