To say that Denton has a tough time of it in the nick is an understatement. It’s especially uncomfortable as we’re so unsure of her innocence. Not only is there the claustrophobic ‘yes/no’ monotony, rice poo-ding, and lack of keyboard facilities, but also the challenge of having two inmates attempt to break her hands with weights, only to then have two guards scald those same hands with boiling water.

Good lord, that was utterly horrific. What is it with Jed Mercurio and hand mutilation?! It feels like only yesterday he was trying to lop Arnott’s digits off with a bolt cutter in Series 1.

Speaking of the first seris, outside chokey there’s a familiar face at Police HQ: Craig Parkinson’s DI ‘Dot’ Cottan.

Cottan, let’s not forget, was arguably the most rotten character of Series 1 by being so closely affiliated with its chief villain, an angry Glaswegian golfer/gangster. That he’s got a cushy job as a DI in AC-9 shows that there’s seldom justice in Line of Duty land. Corruption runs like Japanese knotweed through the force. Is he still a duplicitous crook? Or has he changed his ways? Right now we can only be sure of one thing: like Arnott says, he’s still a wanker.

Arnott and Fleming can’t exactly hold themselves to higher moral authority. Fleming’s affair with Richard Akers has the potential to derail the entire inquiry after she and Arnott decide to bury the fact that Jane Akers, killed in the ambush, tried to call Fleming on the night of the attack. That’s the twisted beauty of Line of Duty, it repeatedly confounds your moral barometer.

Surely everyone’s villainometer is swinging toward reptilian Deputy Chief Constable Dryden (Mark Bonnar), who’s caught in a speeding points scandal, and attempts to distract press attention from himself by putting the spotlight on Denton.

There’s more to that speeding scandal than meets the eye. The revelation that Dryden had a five-year affair with Denton (celeb couple name, ‘Denden’), and that someone with influence is trying to silence her certainly indicates that Dryden – and his fancy biscuits – is up to no good.

But painting him as the de facto baddie now, at only the halfway point, is premature. If this show has taught us one thing it’s that we shouldn’t try to second guess it. It’ll only make the twists and turns that more shocking.

Oh, and it’s also taught us not to eat your first meal in prison. So that’s two things.

Aired at 9pm on Wednesday 26 February 2014 on BBC Two.

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