'Line Of Duty' series 6 finale: Six questions that need answering in the last episode

It wouldn’t be the week leading into a Line Of Duty finale without a prison transport van load of questions.

We are close to the end of series 6 of writer/creator Jed Mercurio's BBC drama, with episode 7 airing BBC One at 9pm on Sunday night.

An average of 11 million viewers watched the penultimate episode, breaking the previous record for the show, and that is expected to be topped this weekend.

But will the audience get the answers to the questions they have been looking for? Or will Line Of Duty leave us all alone in a lorry park, wondering what the heck is going on?

Here are the big questions swirling around LOD fans' brains as they await the final episode in the series.

*WARNING: this article contains spoilers for series 6 of Line Of Duty*

1. Will Jo Davidson survive the series?

The AC-12 team of Superintendent Ted Hastings (Adrian Dunbar), DI Kate Fleming (Vicky McClure), DI Steve Arnott (Martin Compston) and DC Chloe Bishop (Shalom Brune-Franklin) have brought in DCI Joanne Davidson (Kelly Macdonald), who sat anxiously in her cell at the end of episode 6 wondering when that nasty pair of prison guards, clearly in the pocket of the organised crime gang (OCG), are going to strike.

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Davidson ("I'm not a bent copper, I'm just doing everything the OCG tell me") has done well to last this far into the series, but could her time be at an end?

As every viewer knows, prison is the least safe place to be in Line Of Duty land.

2. Who is Davidson's father figure?

Last week, it emerged that not only is Davidson related to former crime boss and paedophile Tommy Hunter (Brian McCardie), he was her uncle AND her father, something poor Jo only learned in her grilling at AC-12.

Read more: 'Line Of Duty' viewers spot new detail about Jo Davidson's past

Earlier in episode 6, she had told Kate that the man she thought was her father was a bent copper, but who could that be?

If you go through the Line Of Duty rogue's gallery, there are a few contenders — Chief Constable Phillip Osbourne (Owen Teale),DCC Mike Dryden (Mark Bonnar) or the deceased ACC Derek Hilton (Paul Higgins) from series gone by.

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3. Is Marcus Thurwell really dead?

Another candidate could be former DCI Mark Thurwell, played by James Nesbitt (well, I say "played" but the actor has done nothing more than pose for a few photographs so far), but he is perhaps too young to be the person she thought was her father.

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At the end of last week's episode, Thurwell's body turned up, along with his wife's, during a raid at his last known address by Spanish police.

Surely Mercurio wouldn't bring in Nesbitt just to have a headshot and a holiday snap taken, fans have howled. But, you know what, that's exactly the kind of thing he would do.

4. Who is 'H'?

It’s a question that has burned away in the fiery heart of Line Of Duty ever since Kate tried to teach the alphabet to a dying DI Matthew "Dot" Cottan (Craig Parkinson) in the phenomenal ending to series 3.

There is the distinct possibility that the identity of "H", or the "Fourth Man", as Ted likes to call him, could be bound up with Davidson's past. Could her father figure be the kingpin connecting police corruption to the OCG?

Read more: 'Line Of Duty' season 6 finale trailer teases capture of H

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It's doubtful Mercurio will answer the "H question" in the series finale, but it might do the show some good if he did - it often feels like the mystery has held Line Of Duty back in some respects - it's at it's best when it concentrates on a rollicking story and tense set-pieces, be they action scenes or AC-12 interviews.

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But if the chase for H is your thing, your suspects are as follows: Ted, Osbourne, Thurwell, Davidson, DCS Patricia Carmichael (Anna Maxwell Martin) or AC-12's cyber crime tech whizz Amanda Yeo (Rosa Escoda).

Okay, I threw that last one in to check you were paying attention. Amanda is brill. If she is H then I won't watch another episode of Line Of Duty again ever.

5. Why was Gail Vella killed?

The Murder Investigation Team (MIT) probe into the murder of journalist Gail Vella (Andi Osho) hasn't borne much fruit, understandable when Davidson has been scuppering every lead.

We know she was killed because she was getting close to exposing links between crooked cops and the criminal underworld, and that she was looking into the dodgy police investigation into the murder of Lawrence Christopher, but what exactly did she uncover?

Quiz: How much do you know about ‘Line Of Duty’?

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While the identity of H may be left hanging, this feels like a question that will be answered in episode 7, as it is the narrative that has driven the series.

Thurwell, Osbourne and DSU Ian Buckells (Nigel Boyle) are all linked to the Christopher case - chances are Vella unearthed dirt on one, some or all of them.

6. Whose body is under the OCG gun workshop?

Last week, Kate and Steve twigged that the OCG weren't rushing to move the gun-making equipment from their workshop, but something else. It's time to dig up the floor.

But whose remains will they find underneath?

We don't have long to wait to find out...

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