DCI Joanne Davidson — who plays the new 'Line of Duty' cop?

Kelly Macdonald as DCI Joanne Davidson in Line of Duty
DCI Joanne Davidson, played by Kelly Macdonald, comes to the attention of AC-12 in Line of Duty. (Image credit: C) World Productions - Photographer: Steffan Hill)

DCI Joanne Davidson is played by Trainspotting star Kelly Macdonald in Line of Duty Season 6.

And, as the new series begins on BBC1 on Sunday March 21, DCI Joanne Davidson is the latest 'dodgy' cop to come under the scrutiny of dogged anti-corruption unit AC-12.

But could mysterious DCI Joanne Davidson prove too tough a nut for them to crack? Is she actually corrupt?

Here’s everything we know about her…

Who is DCI Joanne Davidson?

Kelly Macdonald in Line of Duty.

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

DCI Joanne Davidson has recently been brought in to oversee Operation Lighthouse, an unsolved investigation into the murder of journalist Gail Vella (I May Destroy You’s Andi Osho). 

“She's a tortured person and lonely, and, as the series develops, you find out more and more about why she is the way she is,” says Macdonald. 

“This character has got an incredible story, there's a lot in there, so it was a great opportunity.”

Is Joanne corrupt?

All will become clear as the series unfolds! 

Joanne comes to AC-12’s attention when she takes a police convoy to follow a lead into a possible suspect. But when she spots an armed robbery taking place, she orders the police convoy to stop to investigate, potentially putting the murder enquiry into jeopardy. But is there an ulterior motive to her actions?

“She is enigmatic, a bit of a mystery and hard to pinpoint,” says Macdonald. 

“People don’t know whether they can trust her or not and that carries on throughout the show…”

Will Joanne be interrogated by AC-12?

The anti-corruption unit will be hoping to get her in their clutches. Joanne also carries out interviews of her own during the murder investigation and Macdonald admits those scenes were tough but rewarding.

“The writing is just so incredible and there's a lot more to it than just the ‘lines of duty’, but I did worry before and during filming about the density of the police dialogue,” says Macdonald. 

“That was what I was scared of, because I knew that would be a struggle for me. There are a lot of facts and especially when you're in an interview situation, if you're on that side of the table asking the questions, it's really challenging.” 

Vicky McClure and Kelly Macdonald in Line of Duty.

Joanne becomes a focus for AC-12 in the new series on BBC One and BBC iPlayer.  (Image credit: C) World Productions - Photographer: Steffan Hill)

Where have I seen Kelly Macdonald before?

The actor came to fame in Trainspotting before starring in the likes of No Country for Old Men, Nanny McPhee, Harry Potter and Brave on the big screen. She has also had key roles on TV in crime thrillers Giri/Haji and The Victim and starred in all five series of Boardwalk Empire as gangster’s wife Margaret Thompson.

But Line of Duty has been a career highlight for her.

“It is completely nerve-wracking to become a part of a show that is so well loved across the board, and the guest lead status does feel pretty momentous,” she says. “It's very flattering and exciting. It was a bit like being the new James Bond!”

When can I watch Line of Duty Season 6?

The new seven-part series of Line of Duty airs on Sunday March 21 on BBC1 at 9pm and will also air on BBC iPlayer, where you can also catch up with the previous five series.

Is there a trailer for Line of Duty Season 6?

The teaser shows AC-12’s ‘Gaffer’ Superintendent Ted Hastings (Adrian Dunbar) saying that the murder of Gail Vella is this force’s highest profile investigation, while Joanne appears angry that Gail’s life has been cut short and whoever did it has got away with it. 

Hastings says they have to discover whether police corruption has contributed to the murder remaining unsolved. Joanne then has an awkward conversation with DS Steve Arnott (Martin Compston) and tells him he should investigate, while Joanne later vows “I had nothing to do with it…” as DI Kate Fleming (Vicky McClure) says, “All I know is, somebody is behind all this”. 

Amid scenes of gunshots and car chases, Joanne is shown holding her hands up before Hastings ominously says, “When did we stop caring about honesty and integrity?” 

And, in a final twist, AC-12’s newest recruit DC Chloe Bishop (Shalom Brune-Franklin) says, “Do you still believe there is a fourth man out there?” referring to the group of four corrupt figures known as ‘H’. As Steve says, “Man, or woman?” the camera cuts to Kate…

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.