Duty Reablement Line What has happened in the five seasons so far? Plot explained

It’s been two years since Line of Duty finally hit our screens – so you’d be forgiven for missing out on the exact spot where we left police corruption jerk Jed Mercurio at the end of the run finally.

But with the new series finally ready to start this week it’s important to stay up to date, with a number of plot points from the previous five seasons linked to coming back into play – especially in terms of ‘H’ identity , the last man (or woman) standing from a quarter of deep-rooted corrupt copper in the Chief of Police.

To help you out, we’ve repeated the main events from each of the previous series below – read on for everything you need to know about what’s on has happened so far in BBC drama.

What has happened in Line of Duty so far?

Season One

The first series introduced us to the three characters that have been at the heart of the drama ever since: Superintendent Ted Hastings (Adrian Dunbar), chief of the Anti Corruption 12 Unit (AC-12), Steve Arnott (Martin Compston), a recent move from the Counter-Terrorism Unit, and Kate Fleming, an AC-12 officer who specializes in undercover work.

The task for the first-run AC-12 was to investigate the recently named Tony Gates (Lennie James) – who had raised suspicions because of his high grip rate.

It emerged that Gates had agreed to help his girlfriend Jackie get out of trouble after ‘hitting a dog’ while driving under the influence, but what he did not say she told him that what she had deliberately run over herself was an accountant after he found out she was washing money for local gangster Tommy Hunter.

Naturally, things did not end well for Gates – who was blackmailed and framed by Hunter after the last man killed Jackie. Towards the end of the series, Gates took his own life after directing an AC-12 to Hunter and successfully seizing it.

There was still time for one more announcement, however – it was finally revealed to the audience that DS Matthew “Dot” Cottan (Craig Parkinson), one of Gates’ sub-officers, was the a corrupt officer named ‘The Caddy’ and that he had been working secretly for Hunter – eventually helping him into a witness protection scheme.

As the season draws to a close, AC-12 remains unaware of the Dot bhra detection

Season Two

Keeley Hawes as DI Lindsay Denton in line of duty

In season two the most memorable guest star of Line of Duty has been introduced to date – Keeley Hawes as DI Lindsay Denton, the only survivor of an armed attack on a police convoy that had been carrying defense evidence.

Naturally, AC-12 suspected that Denton had been acting as an internal defender, and she became the subject of intense scrutiny – although she often got a first hand.

It eventually emerged that Tommy Hunter was the protected witness – and that it was Dot who devised the attack on the convoy with the intent of murdering Hunter in order to defend himself, on in case his cover was blown.

Denton wasn’t completely innocent – she had been a supporter after being convinced of Hunter’s evil, but she didn’t know she would be framed for the attack.

As the series came to an end, she was convicted of murder conspiracy, and Dot – who had already been assisting AC-12 with their investigation – was permanently invited to the team, ironically accused of finding the identity of the bent copper known as “The Caddy”…

Season Three

Duty Line Series 3


The big guest star at the start of series three was Daniel Mays, playing Sergeant Danny Waldron ‘s armed response team leader – but in a big turn, he didn’t even make it to the end of the first program.

Waldron had a list of names of people in various power positions who had sexually abused his and his classmates as a child and intended revenge, but was killed by one of his players. itself in the process.

Before he died, he had tried to give AC-12 a copy of his list, but was destroyed by Dot before Arnott could get his hands on it.

Then came the remarkable return of Lindey Denton, who was convicted of being overturned on appeal, forcing her to support Arnott in getting to the bottom of a child abuse case.

In doing so, she discovered that Dot had been in a corrupt state all along, and as a result there was a pause between the two which ended up being fired. dead – although thankfully she had delivered a digital copy of Waldron’s anti-speech list to AC-12 in advance.

At the same time, Arnott was designed as the interior by Dot, but Cottan’s plan came back and his true identity was revealed in a grand interview – leading to an impressive chase while he trying to escape.

At the end of that chase, Dot finally died in incredibly heroic circumstances by jumping in front of bullets from a mystery attacker to save Fleming’s life, recording his ‘Dying Declaration’ for his colleague before he died.

Season Four

Thandie Newton appears in Line of Duty on BBC One


Season four introduced a guest star another big name to the mix – this time in the form of Thandie Newton as Roz Huntley, a detective who was overseeing serial kills.

Her behavior had raised alarm bells for forensic expert Tim Ifield (Jason Watkins), who informed AC-12 that he thought something was wrong in her study – and not long after that he turned dead, not to mention missing three fingers.

Huntley later admits she was responsible for Ifield’s death after she was accidentally killed in a fight, and was jailed.

Meanwhile, Arnott is critically injured after being pushed downstairs by a mystery attacker – leaving him in a wheelchair, while we finally learn the content of Dot’s death proof from end of season three.

It turned out that Kate had been told that there was a corrupt police officer, codenamed ‘H’, who was deeply rooted within the force and who was the main master behind a major conspiracy.

Naturally, anyone with a surname starting with H became a suspect, including Ted Hastings himself, as well as ACC Derek Hilton – although the latter was killed at the end of the day. -series in apparent suicide.

Season Five

Line of Duty S5 - Episode 6

This brings us to the latest series – where Stephen Graham took the lead role as a guest, playing the hidden cop DS of John Corbett, who appeared to have gone wrong while infiltrating an organized crime group ( OCG).

Corbett was assigned to find an ‘H’ identity while working undercover, but eventually became the newest guest star without making it through an entire series – killed after for crossing with Lisa McQueen (Rochenda Sandall), a member of the RSE.

Meanwhile, Hastings had emerged as a key suspect in the ‘H’ investigation – largely due to complex links between himself and Corbett in the past – and was grounded by DCS Patricia Carmichael (Anna Maxwell Martin) after being suspended from office.

Eventually, Hastings appeared to have been acquitted after he persuaded lawyer Gill Biggeloe, who found out he was trying to plot it – though it’s fair to say that a few question marks still hanging before the end of the series.

One of the biggest revelations at the end of series five related to new information about Dot’s death confirmation – it turned out that he was communicating (using Morse code) that there was really only one four high quality police staff working with the RSE.

We now know that three of them were Dot himself, Gill Biggeloe and Derek Hilton, but what is the fourth? It’s still anyone’s blows.

In addition, at the end of the series we saw Corbett murderer Ryan Pilkington enroll as a student police officer – suggesting that AC-12 will still have enough curved cops to deal with for a while yet…

Line of Duty begins on Sunday 21 March at 9pm on BBC One. Check out the rest of our Drama coverage, or check out what else goes on with our TV guide.