Yahoo News Line of Duty series 4: Everything you need to know
It was BBC Two's most successful drama series for almost 15 years – and now Line of Duty has risen up the ranks, earning a promotion to BBC One.
Yes, AC-12 are back for a fourth series – and you know what that means. More bent coppers, more nail-biting interrogations and more of Ted Hastings (Adrian Dunbar) calling slippery suspects "fella".
Here's everything we know so far about the unit's next investigation, starting with a recap of where we left off...
Line of Duty series 4 air date: So when's it back?
AC-12 were back in action as of August 2016, with the new series premiering on March 26 at 9pm on BBC One. That's a Sunday night (cosy!) and Mother's Day to boot.
We got our first proper teaser trailer in February, with AC-12 are hot on the case of a new quarry who's insisting she's "not corrupt" – maybe the mega-twist this time round will be that she's actually clean?
Line of Duty series 4 cast: The good, the bad and the ambiguous
Martin Compston (DS Steve Arnott), Vicky McClure (newly-promoted DS Kate Fleming) and Dunbar's Supt. Hastings will all be back, fighting the good fight.
They'll be joined by an old face – with Maya Sondhi back as PC Maneet Bindra – and a new recruit – Royce Pierreson is the (trustworthy?) DC Jamie Desford.
And their latest target? One DCI Roz Huntley, played by BAFTA-winning actress Thandie Newton – following in the footsteps of AC-12's former quarries Lennie James, Keeley Hawes and Daniel Mays.
Jason Watkins – another BAFTA winner – will play Huntley's colleague, forensic coordinator Tim Ifield, with The A Word's Lee Ingleby cast as her husband Nick.
No word yet on if Neil Morrissey will reprise his recurring role of dirty DC Nige... but we've got everything crossed.
What happened in Line of Duty series 4, episode 1?
Roz Huntley's high-profile investigation into a string of abductions and murders leads her to Michael Farmer (Scott Reid) and if she was going to pin the crimes on anyone, Michael – a convicted sex offender with learning difficulties and no alibi – would be the perfect patsy.
But did she, in full possession of the facts, fit up the wrong man, or – under pressure and having convinced herself that she'd found the right man – did she simply ignore what she considered to be the unnecessary interference of an overly-officious colleague?
Tim Ifield (Jason Watkins) won't back down, sharing his suspicions about Huntley's conduct with AC-12, so a frustrated Roz decides to pay Tim a visit at home and things spiral quickly out of control. A verbal clash between the two escalates into a physical confrontation. In the aftermath, Roz lays prone, apparently dead, with Tim her accidental executioner.
But just as you start to believe that writer Jed Mercurio's pulled his old trick again, offing his star name in the first episode, a final twist reveals that she's alive after all...
What happened in Line of Duty series 4, episode 2?
In Chapter Two, it was revealed that Roz had survived her encounter with Tim – after waking to see him bearing down on her with an electric saw, she pushed back at her assailant, with the saw slicing open his throat.
Struggling, a dying Tim then tried to contaminate Huntley with his blood, and to get her skin under his fingernails. Unfortunately for Tim, and for AC-12, a canny Roz cottoned on to Tim's ploy and amputated his fingertips post-mortem as part of forensic clean-up. Grim.
Roz also pocketed Tim's phone and laptop – taking with her any footage of the incident – and was able to swap out a sample of her blood taken from Ifield's kitchen with a vial of his own.
Huntley was briefly taken off Operation Trapdoor – but after planting a sample of Tim's DNA on the corpse of one of the victims, she appears to have found herself a new fall guy and is back in control.
But for how long?
What happened in Line of Duty series 4, episode 3?
Oh wow.
Fans were left shook by a nail-biting third episode, which saw Steve left for dead by a masked assailant, who may or may not have been Roz Huntley's shifty husband Nick (Lee Ingleby).
The mystery surrounding Tim Ifield's demise, and his relationship with Hana Reznikova, deepened - as it was revealed they had a sexual relationship and she ended up in the frame for his murder.
Meanwhile, Kate closed in on Roz and her forensic foul-up, after the DCI fiddled with blood samples taken from Tim's flat in an attempt to conceal her presence there.
What happened in Line of Duty series 4, episode 4?
Steve lives! Despite sustaining serious injuries from his fall - including a fractured skull - Arnott lived to fight another day.
Meanwhile, AC-12 suspected Nick of being Balaclava Man - but he had a solid alibi for the night of Leonie Collersdale's disappearance, when her masked assailant was captured on CCTV.
Still, it looked as though our heroes had Roz on the ropes - for framing Michael Farmer, and interfering with the forensic evidence in Tim's murder - until she capitalised on Hastings' sexism to accuse him of leading a misogynist "witch-hunt" against her.
In one final twist, it was revealed that apparently loyal PC Maneet Bindra (Maya Sondhi) had actually betrayed the team, handing over important files to slimy ACC Hilton (Paul Higgins). Why, Maneet, why?
What happened in Line of Duty series 4, episode 5?
Roz might've dealt AC-12 a blow, but is still suffering with a serious wound she sustained during her fight with Tim – the injury, it's revealed, is infected with MRSA and she has to have part of her arm amputated. Cripes.
Things aren't looking great for Nick Huntley either. AC-12 dismantles his alibi for the night that Balaclava Man victim Leonie Collersdale disappeared, and he ends up being arrested for Tim Ifield's murder - by his own wife!
So who is Balaclava Man? Is it Nick, or could it be smarmy solicitor Jimmy Lakewell (Patrick Baladi) - who had a prior connection to Michael Farmer?
It now appears that the killings of Leonie and the other victims are linked to events that occured back in the first series of Line of Duty – with Leonie's body being stored in a manner similar to Jackie Laverty's.
Jackie, in case you've forgotten, was the mistress of series one's corrupt cop Tony Gates (Lennie James), who was murdered by masked thugs. Now it appears the same criminals are behind the Balaclava Man killings. But why? What's the motive?
Meanwhile, we finally heard the dying declaration of bent copper DI Matthew 'Dot' Cottan - in which he was named a senior officer - someone above the rank of Inspector and with the first initial 'H' - as being involved in organise crime.
It's obviously Hilton who's the Big Bad, but he's trying to shift the blame to Hastings...
Line of Duty series 3: What the heck happened again?
It finally happened. Dirty, devious DI Matthew Cottan (Craig Parkinson) was taken down in Line of Duty 's third series finale – but found a little redemption in his final moments.
The writing was on the wall for Dot when he was brought in for interrogation by his colleagues at AC-12 – with Kate Fleming (Vicky McClure) refusing to believe that her framed friend Steve Arnott (Martin Compston) was the corrupt officer known as The Caddy.
The ordinarily unflappable Cottan started to sweat as the evidence piled up against him – with his old frenemy Nigel Morton (Neil Morrissey) providing evidence linking Dot to paedophile mobster Tommy Hunter.
Utilising one of the corrupt officers in his employ, Dot staged a daring escape from AC-12, with Kate in hot pursuit.
When the two finally faced off, Fleming urged Cottan to confess and give up the names of "all the monsters [he'd] protected" - but before he could make a decision, another ally of Dot's took aim at Kate... and he threw himself in front of the bullets, sacrificing his own life to save her.
Cottan made good in his dying moments, giving a full confession and providing crucial evidence in AC-12's case against the wicked ex-copper Fairbank (George Costigan).
Line of Duty investigation: What did Roz do (and did she really do it?)
Series four begins with Roz and her team in the thick of a career-defining case, known as Operation Trapdoor.
Under intense pressure to catch the culprit and prove herself to her superiors, and in conflict with Watkins' character Tim, it's not long before AC-12 decide to probe her handling of the investigation.
All sounds fairly straightforward. We're confident the investigation will resolve itself quickly and amicably with a minimum of fuss... and absolutely no mega plot twists.
Of course, part of what we love about Line of Duty, of course, is the labyrinthine plotting – with each series cleverly weaving into the previous as part of an increasingly complex web.
Dot was only part of a vast criminal conspiracy – though, when Digital Spy spoke to writer Jed Mercurio back in April, he wouldn't comment on how much of that conspiracy was yet to unfold.
"We're only really at the beginning of the process on series four," he said at the time. "So at the moment, it's impossible to say whether it'll relate in any way to what's gone before or not."
Line of Duty deaths: So who's gone for good?
Bar another major twist, Dot is done... and though we're still struggling to accept it, Keeley Hawes won't be back as the morally dubious but endlessly watchable Lindsay Denton.
Because, y'know, this happened...
Line of Duty series 5: What does the future hold?
No-one's safe on Line of Duty (one alternative ending to the last series even offed Steve Arnott!) but clearly AC-12 will continue to operate on some level, because the Beeb's already ordered a fifth series.
"I'm certainly not inclined to stop doing Line of Duty," Mercurio told us when asked about the show's long-term future.
"It's great to be involved in a series that gets such a fantastic response from [casual] viewers and fans alike. I hope it continues."
Want up-to-the-minute entertainment news and features? Just hit 'Like' on our Digital Spy Facebook page and 'Follow' on our @digitalspy Twitter account and you're all set.
You Might Also Like
