Line of Duty recap: 5 important questions we need answering after episode 2

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The ‘undercover’ police officer has convinced Steve Arnott (Martin Compston) he’s still on the right side of the law, committing heinous crimes in a bid to eventually expose corruption at the top levels. But has he been turned or not? And just who did PC Jane Cafferty (Sian Reese-Williams) identify as the copper who recruited her? Read on for our breakdown of the big questions raised in episode two…

1. Is John Corbett telling the truth?

Episode one may have introduced the balaclava boss as a chilling figure – an undercover cop lured in by organised crime – but its follow-up sowed seeds of doubt in our minds.

We saw a different side to John; a family man who desperately misses his wife and kids and is fighting a desperate battle to expose powerful, compromised policemen. As Steve edged closer to the balaclava gang, following Maneet’s instructions to make contact, John identified an ally, kidnapping the AC-12 officer and offering his side of the story. Steve was convinced by seeing him pay off Cafferty and, unbeknownst to Ted or DI Kate Fleming (Vicky McClure), made a pact to help him. (John also took the opportunity to orchestrate Lee's arrest after the balaclava man started shooting him suspicious looks).

But is the undercover cop telling the truth or selling Steve a lie? Does he have the “squeaky clean” AC-12 officer exactly where he wants him, offering him the chance to kick against the authority Kate now has over him? Or is John a lone agent fighting to expose a cohort of corrupt officers that includes Ted and Det Supt Alison Powell (Susan Vidler)?

As ever, it’s a hard one to call.

Which police officer did Jane Cafferty identify as her recruiter?

The closing moments of episode two saw PS Cafferty in an interview room where Kate had laid out photos of police officers from AC-12's investigation board. Each has confirmed or possible connections to organised crime.

Among the cops were ACC Hilton (from series four), DI Matthew “Dot” Cotton (series one to three), DS Jeremy Cole and Manish Prasad (both series two) and CS Patrick Fairbank (series three), but Kate added two mysterious sheets of paper from a drawer – presumably two coppers who were once mooted to be H. The names on that list included Roz Huntley, Ted Hastings and Lester Hargreaves, Chief Superintendent of Murder Squad.

But who did Jane pick? It's a rare occasion when AC-12 know something that Line of Duty viewers don't. Kate and Steve shared a knowing look which likely rules out Cole and Prasad – fairly insignificant characters in the grand scheme of Line of Duty – and we can probably strike Roz Huntley from the possible culprits, too.

Which leaves some major players – some deceased, some very much active within the force. Whoever Jane picked, we were left in no doubt that Ted was unhappy with the line of questioning (how many times did the camera pan to his anxious face peering at the interview room?) Which leads us to…

Is Ted Hastings corrupt?

We asked this question after episode one and we’ll address it again here. Jed Mercurio has gone out of his way to suggest AC-12's boss is complicit in police corruption, stacking up yet more clues in this second instalment. After four series spent believing Super Ted is the show's moral core, it's a bitter pill to swallow.

But are we being led up the garden path? We can't ignore the clues so pointedly dropped into the script. In episode one, we saw the phone of Rochenda Sandall's gang operative Lisa McQueen (ringing) right before the camera switched to Ted (making a phone call). The two never spoke (significant) but we all know what was insinuated. And in episode two, the hints came thick and fast:

• Jumpy Ted was very interested in who Jane identified as her police contact.
• Thanks to John, we were also invited to question why the Superintendent shot dead a balaclava man in AC-12's offices at the end of series four when he was surrounded by authorised firearms officers. The dead man has since been identified as an active member of John's criminal outfit. Was Ted trying to silence him?
• John wasn't the only one communicating on instant messenger in episode two. Dejected after a meeting with his soon-to-be-ex-wife, Ted was seen in his hotel room browsing a brochure from investment manager Mark Moffatt (more on that below). The camera then zoomed out to show us his laptop, just as an instant message popped up below a line of text. Who is Ted chatting to? Surely it's more than a coincidence that this is exactly how the mysterious "H" chooses to make contact?

Which all rightly leads us to doubt Ted's integrity. But – a question for you, Line of Duty fans – can we really expect the overarching question to four series of Jed Mercurio's twisty thriller to be answered this simply? Surely not. With four more episodes of series five to go, either the mystery of "H" will be solved right here (culprit: Ted) and this drama will become something very different. Or Ted is a big red herring. Our hopes are pinned on the latter.

What's up with Steve?

A good chunk of time has passed since Steve was thrown down a stairwell by a balaclava man, but he's still suffering the effects. He's got a sore back (not helped by dump tackling Vihan Molhotra in episode one) and is living a lonely life.

But is there more to it? Episode two saw him reconnect with ex-girlfriend Sam Railston (Aiysha Hart), but when she asked him up to her flat, Steve looked a bit spooked and made his excuses. This is not the Steve we've come to know – the man who has slept with both colleagues and witnesses in his time. Has his accident left him with some issues downstairs?

Who is Mark Moffatt and can he be trusted?

We've known about Ted's financial difficulties since series two – an ill-advised investment in an Irish housing estate, the Kettle Bell Complex, which led to the breakdown of his marriage, the loss of his home and his current unpaid hotel bill. But he was offered a way out in episode two, approached by a man called Mark Moffat (Patrick FitzSymons) – a retired DCI who we've seen before as Roz Huntley's Police Federation Rep in series four:

He and Ted had some testy exchanges during Roz's interviews – Ted slapped him down for not addressing him as "Sir" – so it seems a bit fishy that he's now a friendly retired chap sweeping to the AC-12 boss's rescue who just HAPPENS to be working on the same property business and just HAPPENS to be offering compensation. It's all too neat. And Ted wouldn't be the first copper in financial difficulties to be approached by sinister parties (remember Molhotra was first lured in by a promise to help with his gambling debts?)

Our money is on Mark Moffatt having an ulterior motive...

Line of Duty continues on Sundays at 9pm on BBC1