'Line Of Duty' series 6 episode 2 recap: Key character returns who will have fans fuming

One of the major appeals of Line Of Duty is that it waits for no one.

Its often heralded bombardment of police operations jargon should bamboozle viewers, but instead it grips them even tighter.

Half the audience Googles as they go, the other is happy for it to sail over their heads.

Read more: ‘Line Of Duty’ series 6 episode 1 recap

You see, it doesn’t really matter if you don’t know exactly what a CHIS or an AFO is when you’re swept up in the drama.

But even by Line Of Duty standards, the second episode of series 6 is a brain-melter, with plot developments - many of them off-screen - sprayed all over the place like graffiti in a dodgy underpass. But more on that dodgy underpass later.

Here are the major talking points from Line Of Duty series 6 episode 2. *WARNING: spoilers below*

1. 'I’m interested in one thing and one thing only, and that’s bent coppers.'

Time for millions of LOD fans to hurl the remote at their tellies… that nasty piece of work Ryan Pilkington is back.

As trailed at the end of the last series, organised crime gang (OCG) member Pilkington (Gregory Piper) has infiltrated the police force… and just where has he ended up? On Operation Lighthouse, of course, the rather dodgy looking investigation into the murder of TV journalist Gail Vella (Andi Osho).

His first appearance in series 6 is at the scene of another murder, that of criminal Carl Banks, where PC Pilkington has a chance to admire the killer’s handiwork, given he dished out the same slit throat punishment to undercover cop DS John Corbett (Stephen Graham) in the previous season’s standout moment.

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Or is he admiring his own handiwork? Did Pilkington kill Banks to stop him blabbing about Vella’s murder? He is the officer who finds the smoking gun - I mean, knife - after all. No one believes the killing was carried out by the CHIS, Alastair Oldroyd, whose body is also conveniently in the morgue, do they?

DI Kate Fleming (Vicky McClure) gives Pilkington the first of about 30 double takes, but hasn’t quite worked out why his sweet innocent face rings a bell. It’s slipped her mind that she interviewed him back in series 1 when he was just 13 and shipping burner phones for crime syndicate kingpin Tommy Hunter.

Perhaps Steve Arnott (Martin Compston) - newly promoted to Detective Inspector - will have a better memory, given little Ryan once tried to peel off his fingers with a bolt cutter.

2. 'The truth is, it’s all getting a bit tense.'

It’s no coincidence Pilkington has been assigned to the Murder Investigation Team (MIT), as his main job appears to be keeping DCI Joanne Davidson (Kelly Macdonald) in check on behalf of his crime bosses.

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She remains an elusive figure. She’s clearly in the pocket of criminals, as is anyone in Line Of Duty with a pay-as-you-go phone, but her window-banging from inside her car that ends this episode demonstrates this isn’t what she wants for herself, and that the OCG have something on her that they are fully exploiting.

One of AC-12’s former finest is also proving hard to pin down...

3. 'You always choose a right s**hole.'

The most quotable sequence from episode 2 is when Steve and Kate retreat to AC-12’s designated informer underpass to talk strategy.

“Just like old times,” says Steve, but Kate is in no mood for reminiscing, perhaps because Steve never brings her coffee to the graffiti-strewn location the way good old DI Matthew "Dot" Cottan did.

It would be just like old times if Kate proceeded to carry out an undercover sting and got rumbled within about 20 minutes, which is perhaps why she expresses her reluctance.

‘Line Of Duty’ quiz: Test your knowledge ahead of series 6

“You’re no rat if she’s bent,” Steve replies, referring to Davidson.

But Kate rebuffs Steve’s offer to go undercover, giving her new boss (we know Davidson’s her boss because she calls her “boss” every third word) the heads up on AC-12’s investigation, allowing a crucial evidence-shredding delay from the Deputy Chief Constable (DCC).

“I trusted you, mate,” says Steve, perhaps too impulsive to realise his former partner is playing the long game.

As her old gaffer, Superintendent Ted Hastings (Adrian Dunbar) says: "Kate has made her bed, now she’s gotta lie in it.”

4. 'We’re detectives too, you know, in case you haven’t noticed.'

And so AC-12 reaches for its Reg 15 and Davidson is brought in for the first set-piece interview of the new series.

It’s an interesting stand-off because she is a formidable adversary for Ted and Steve, mainly because, like the audience, they can’t quite get a steer on her character.

Instead of fighting fire with fire and going all-out Lindsay Denton on the pair, she cleverly agrees with what they are saying, which must be a first for her inquisitors.

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This is because Davidson has a back-up plan, and it’s all about throwing her ex-partner and ex-colleague PS Farida Jatri (Anneika Rose) under the bus.

“God give me strength, I don’t know who to believe,” mutters Ted, speaking for the audience.

But we know what’s coming. Davidson wins and Jatri loses (“That’s what happens to a rat.”) and that spine-tingling tinkling piano theme kicks in.

Episode 2 verdict: Viewers impatient for the first of this series's huge shocks are going to have to wait a bit longer.

This isn't necessarily a bad thing, as the show has always depended as much on its build-up of tension as on its explosive revelations.

The fireworks will come later, of that we can be sure. Until then, try to spot the bent coppers from the slightly less bent coppers and enjoy the jargon, Google or no Google.

Watch: Line Of Duty series 6 teaser