'We're going to have H on the sofa next week': Alison Hammond confirms the fourth person WILL be revealed during Sunday's Line Of Duty finale

It's the question that has been haunting Line Of Duty fans, and Ted Hastings, for several series - who is the remaining fourth person?

And Alison Hammond confirmed their identity will finally be revealed during Sunday's finale as she announced H will be appearing on This Morning next week.

The presenter, 54, signed off from Friday's episode of the ITV show teasing viewers that H will be 'on the sofa' on Monday, joking that she doesn't mean H from Steps.

After running through Monday's line-up, Alison told viewers: 'After Line Of Duty's Sunday night show we're going to have H on the sofa - and it's not H from Steps.'

Her co-host Dermot O'Leary, 47, could not contain his excitement as he leant back and squealed at the exciting news.

There are still several potential characters who could be H including DCS Patricia Carmichael (Anna Maxwell Martin), DCC Andrea Wise (Elizabeth Rider) or even newcomer Marcus Thurwell (James Nesbitt) despite him allegedly dying in a raid.

And even AC-12's own Superintendant Ted Hastings (Adrian Dunbar) and DS Kate Fleming (Vicky McClure) have been tipped as potential contenders.

Alison's update comes after Phillip Schofield nearly let the spoiler slip as he discussed Sunday's highly-anticipated finale on This Morning on Tuesday.

The host, 59, said he had to 'tread carefully' as he announced that he and Holly Willoughby, 40, would be interviewing a 'very exciting guest' next Monday, after the final episode has aired. 

Phillip kept the identity of the star shrouded in mystery, with Holly saying she was relieved it was Phil telling viewers the news and not her, over fear she would reveal a major spoiler.  

Phil said: 'The country is gripped by Line Of Duty we have and all I'm allowed to say is on Monday's show a very exciting guest, pertaining to that show, on Monday.' 

Holly chipped in: 'I'm glad you're saying this and not me because I definitely would have messed that up.'

Phil replied: 'I'm treading the line of what we were told we were allowed to say this morning and I think I've gone right down the middle of it.' 

Showing off her wit, Holly told him: 'Treading the Line Of Duty would be the thing to say.'

To which Phil laughed and said: 'That's exactly what it is. But we do have an exciting guest on Monday.  

A dramatic trailer for the final episode of Line Of Duty released on Monday left fans wondering if the gripping police thriller will return.

It has been five years since anti-corruption police in the AC-12 unit began to hunt a mysterious bent top copper known as H. 

The 30-second trailer seemed to indicate viewers will at last learn the identity of H as the sixth series of the BBC1 show draws to a close on Sunday.

The trailer had an element of finality, prompting fans to speculate it could be the end of Line Of Duty.

Superintendent Ted Hastings, played by Adrian Dunbar, says: 'All of these suspicious deaths were orchestrated by one officer in particular – H, the fourth man.'

The future of the hugely popular drama has been unclear for some time, with the BBC and show creator Jed Mercurio failing to confirm another season.

Speaking about more possible series, Mercurio told Radio Times earlier this year: 'We don't know. Since probably season four, we've been talking to the BBC about the realistic longevity of the series. It's an ongoing discussion is all I can say.'

Line Of Duty continues on BBC One at 9pm.