8 burning questions we have after Line of Duty series 3 episode 4

Firstly, let’s all take a moment to thank our lucky stars that Lindsay Denton is back for series three. Who else punched the air in solidarity as she dispatched nasty Robin with kick-ass precision? But Denton has a hold over Steve Arnott – and while she claims not to enjoy making threats, you couldn’t mistake the look of triumphant glee as she teased details of her phone recording to Arnott’s AC-12 colleagues. But what’s the dirt she has on him? Series two saw the pair get close, but Arnott has always maintained he was “nurturing the trust of the target” (ahem) and did not sleep with Denton. So, what exactly is in that phone recording?

Are Steve’s days at AC-12 numbered? The detective constable is in just about everyone's bad books right now and Gill is out for his blood. Can Ted hold her off with after-hours dinner dates and stolen snogs? “I intend to return to this conversation,” she informed him, ominously. Steve may be Hastings’ most dogged investigator but we have a feeling Gill won’t let go anytime soon – that is unless Ted can provide an adequate distraction…

Dot continues to do a grand job of pulling the wool over Steve’s eyes but how long can he keep it up? With that muttered final word from Waldron and forensics confirming the existence of a list inside the envelope – you know, the one Dot pulled and destroyed – is the Caddy’s cover-up on the verge of being exposed? After all, Dot was the one who searched Waldron’s bedroom and one of these days Maneet will be at her desk to deliver news of the list to Steve, no matter how much Dot tries to keep it “just between us”. And on that subject…

Seriously, for a bunch of policemen trained to sniff out a rat, this lot aren’t half slow to cotton on. OK, us viewers have a head start – we’ve known for an agonising series and a half that Dot is the bent copper known as “the caddy” – but the cracks are beginning to show. From the second post-mortem he failed to order to his softly-softly approach during Nigel Morton’s interview, and his firm words with Kate not to investigate him further, Dot is no longer the cool cucumber he once was.

Granted, all the above are tiny details but the sum of their parts is a giant finger pointing at one person and one person only.

The bodies continued to pile up with tonight's episode introducing social worker Oliver Stephens-Lloyd. Or rather, introducing his case file. Yup, Oliver Stephens-Lloyd was yet another person sniffing around the paedophile ring and snuffed as a consequence. But who killed him and dumped him in the river? The culprit is likely the Big Bad who ordered the deaths of Tommy Hunter and Danny Waldron. Will we ever get to meet him?

Let’s all agree to overlook the daftness of Morton bringing that second phone – his “insurance” – to his meeting with Dot. Implausible, yes – but this is drama, daaarling, and that extra incriminating sim card is yet another means of bringing down Dot. Will Morton hold it back until his hand is forced? Or does he have other ideas up his sleeve?

That handshake, eh? There’s no mistaking what Steve saw – but if Hastings and Fairbank are both Freemasons, it begs the question: how far will they go to protect one another? Fairbank is obviously hiding something. Why else would he have called in his old friend as back up? But Ted Hastings – decent, honourable, principled Ted Hastings – couldn’t possibly be aware of the cover-up, could he? No, it's impossible. But with a team of dogged investigators on the case, surely it won’t be long before Fairbank is implicated. And when he is, where will Ted’s allegiance lie?

“The fingers point at one of our own,” Dot assured Ted in the closing moments of episode four. Indeed. And with the Caddy’s cover foiled, the corrupt copper needs to pin his misdeeds on a new officer. But who will he pick? Steve Arnott, the eager puppy ostracised by his colleagues and operating under the cloud of Lindsay Denton’s botched investigation? An easy target but he’d be small fry compared to Ted Hastings, especially if Dot gets wind of Steve and Kate’s suspicions. With just two more episodes in this series, the game is afoot.

Line of Duty continues next Thursday at 9pm on BBC2

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