‘Line of Duty' Season 6 finale — the burning questions we want answered!

Line of Duty Kelly Macdonald
Line of Duty: what does the finale have in store? (Image credit: C) World Productions - Photographer: Steffan Hill)

Line of Duty Season 6 has kept us on the edge of our seats even more than in previous years, with a host of shocks, twists and curveballs being thrown our way. 

This Sunday, the drama is concluding in epic style as time is running out for AC-12. While the forced retirement of Superintendent Ted Hastings (Adrian Dunbar) looms closer, DI Steve Arnott (Martin Compston) faces possible suspension if he continues to evade a medical review to hide his painkiller addiction. 

Can they and DI Kate Fleming (Vicky McClure) finally crack the Operation Lighthouse investigation into the murder of journalist Gail Vella and unmask the elusive ‘H’ or ‘Fourth Man’, the corrupt police figure linked to organised crime?

Here are six burning questions that need to be answered in the finale…

Who is responsible for the murder of Gail Vella? 

Carl Banks, part of the organised crime group (OCG), appears to have killed journalist Gail and has now been murdered himself. But who ordered Gail’s assassination? She was investigating police corruption concerning historical cases, some of which involved ex-detective Marcus Thurwell (James Nesbitt), who has now apparently been murdered, dodgy cop DCU Ian Buckells (Nigel Boyle), and seemingly shifty Chief Constable Philip Osborne (Owen Teale). Did one of them request the hit? 

“The Vella case is something the police force is struggling to solve,” says the show’s writer Jed Mercurio. “There’s been no closure.”

Who did Joanne think was her father? 

Kelly Macdonald in Line of Duty

Kelly Macdonald as Joanne Davidson in Line of Duty. (Image credit: World Productions - Photographer: Steffan Hill)

Troubled cop Joanne Davidson (Kelly Macdonald) has discovered that murdered crime boss Tommy Hunter (Brian McCardie) was her father as he had raped her mother Samantha, his sister. But who was the ‘bent police officer’ she believed to be her real father? Could he be Thurwell, Osborne, or even Hastings?

“Things have happened in the past,” teases Mercurio. “Joanne is enigmatic…”

What is Carmichael’s motivation? 

DCS Carmichael Line of Duty

Anna Maxwell Martin as DCS Carmichael in Line of Duty. (Image credit: BBC/World Productions)

Formidable DCS Patricia Carmichael (Anna Maxwell Martin) has taken control of AC-12 and shut down their enquiries, particularly those linked to Osborne or the search for ‘H’. Are Pat’s actions down to her jobsworth desire to stick to budget cuts? Or is she protecting a corrupt colleague, or even herself? 

“I wouldn't be allowed to blab, but she’s ready to bust some balls,”  laughs Maxwell Martin. “I love playing Pat, she’s ace!” 

Is Chloe the daughter of Tony Gates? 

Shalom Brune-Franklin in Line of Duty

Shalom Brune-Franklin as DC Chloe Bishop in Line of Duty. (Image credit: C) World Productions - Photographer: Steffan Hill)

Efficient DC Chloe Bishop (Shalom Brune-Franklin) has unearthed vital evidence for AC-12, but fans have been speculating like crazy about her background as series one’s dishonest cop Tony Gates (Lennie James) had two daughters, one of whom was called Chloe... Is Chloe working with AC-12 to atone for her late dad’s shady past, or is she continuing his legacy and leaking information to the OCG?

“Chloe’s eager to prove to her bosses that she was the right choice,” reveals Brune-Franklin. “She’s really trying to impress…”

Is Kate corrupt? 

Vicky McClure in Line of Duty

Vicky McClure as DI Kate Fleming in Line of Duty. (Image credit: C) World Productions - Photographer: Steffan Hill)


An ‘H’ was seen beside Kate on the graffiti in the subway where she meets her AC-12 colleagues. Is this a telling clue? Did the seemingly upstanding cop leave AC-12 and join Operation Lighthouse in order to control the murder investigation for the OCG? And if so, will she be killed off in dramatic style?

“Nobody’s safe, that's what keeps the audience on the edge of their seat,” hints Jed. “It’d be a sad day. But all the cast realise it's possible. We're mates, we joke about it. It's something no one would relish, but everybody would understand…”

Is Hastings ruled out as 'H'? 

Adrian Dunbar in Line of Duty

Adrian Dunbar as Superintendent Ted Hastings in Line of Duty. (Image credit: C) World Productions - Photographer: Steffan Hill)

Although suspicions that Hastings was ‘H’ seemed to have been assuaged last series, his behaviour still gives cause for concern. Did he give money to Steph Corbett (Amy De Bhrún) to ease his guilt over her husband John’s death, or to buy her silence? Why did he really block Ryan’s arrest? 

“We’re looking forward to how it plays out,” smiles Dunbar. “All will be revealed in the fullness of time.”

Where can I watch the finale of Line of Duty?

Line of Duty concludes on Sunday May 2 on BBC1 at 9pm and you can also catch the finale, and the rest of the series so far, on BBC iPlayer.

Caren Clark

Caren has been a journalist specializing in TV for almost two decades and is a Senior Features Writer for TV Times, TV & Satellite Week and What’s On TV magazines and she also writes for What to Watch.


Over the years, she has spent many a day in a muddy field or an on-set catering bus chatting to numerous stars on location including the likes of Olivia Colman, David Tennant, Suranne Jones, Jamie Dornan, Dame Judi Dench and Sir Derek Jacobi as well as Hollywood actors such as Glenn Close and Kiefer Sutherland.


Caren will happily sit down and watch any kind of telly (well, maybe not sci-fi!), but she particularly loves period dramas like Call the Midwife, Downton Abbey and The Crown and she’s also a big fan of juicy crime thrillers from Line of Duty to Poirot.


In her spare time, Caren enjoys going to the cinema and theatre or curling up with a good book.