17/04/2017 10:06 BST | Updated 18/04/2017 06:45 BST

'Line Of Duty' Review: 11 Burning Questions We Have Following Series 4 Episode 4

The tables are turned.

‘Line of Duty’ fans breathed a sigh of relief for Steve Arnott’s survival after last week’s attack.

However, while we could all exhale now that DS Arnott has lived to see another day, Episode 4 brought its own fresh catalogue of shocks, namely...

1. Oh Maneet! WHY, WHY, WHY? This series’ saving grace has been AC-12’s desk-bound support, so why would she suddenly turn turncoat for someone as clearly greasy as ACC Hilton? The most disappointing moment of this series so far was her appearance in the dark doorway, complete with a secret stash of AC-12 intelligence for the ACC’s delectation?

Roz Huntley (Thandie Newton) successfully turned the tables on AC-12

2. Earlier on, it was heavily implied but not confirmed that Nick Huntley was the man who despatched Steve Arnott over the bannisters - can we tick this box?

3. If Nick Huntley isn’t Balaclava Man, why would he don this uncannily popular bit of headwear to despatch Steve Arnott over the bannisters? No matching forensics on his suit here, either - another twist on the way?

4. Roz Huntley might have dodged her husband’s questions about her whereabouts on the night of Ifield’s death, but she’s created a whole new level of distrust with her “confession” of adultery to do it… will this come back to bite her following Hilton’s yucky proposition that she turned down after extracting what she needed from him?

5. “Let me give you another number to be discreet” - Would a high-ranking ACC, even one as greasy as Hilton, really be that stupid, in his extra-curricular pursuit of Huntley? 

6. Her second Reg-15 summons to AC-12 brought an impressive counter-attack by DCI Huntley, accusations of impropriety by AC-12 in general and sexism by Superintendent Hastings in particular, that left them quaking in her wake and their investigation in tatters - will AC-12 work out that only Hilton could have provided her with the smoking gun data?

7. How long has Huntley known about Kate’s AC-12 status? Presumably the latter’s blatant wandering around the building, looking at evidence, talking to fag-break Kevin, couldn’t have helped… 

8. The only hope we have now is the beginning of Roz Huntley’s own destruction, possibly via that still-leaking wound on her wrist and those pills she’s knocking down to assuage the pain. Will this prove to be her undoing?

9. So now we know that Roz Huntley will do anything, ANYTHING, to escape investigation over her handling of the Michael Farmer case. What we still need to know is why she initially pushed for his arrest in the face of Timothy Ifield’s concerns, and will now do ANYTHING to secure his conviction?

10. Can someone just grab her wrist and bring her own wall of defence crashing down? 

11. Some viewers are speculating that Balaclava Man is none other than Hilton himself. That could explain the pressure on Huntley to secure a conviction elsewhere, but… would he really do this in his spare time when he’s not leading the police force and drinking buckets of red wine? Strange, if true. Two episodes to go. 

Catch up with ‘Line of Duty’ on BBCiPlayer.

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