‘Line of Duty’ returns for its fourth series this Sunday evening, which means a reunion for AC-12 in what is, arguably, the finest, most suspenseful, crime drama on British television.
The show, penned by Jed Mercurio (’Cardiac Arrest’, ‘The Grimleys’, ‘Bodies’) has been such a hit on its original home of BBC Two, that it’s now being moved to the flagship slot of Sunday night, BBC One.
For Martin Compston, who returns as DS Steve Arnott, this isn’t the only change. His character faces a fresh challenge this time around, with his newly-promoted colleague, Kate Fleming (Vicky McClure).
“He does have something to prove now he and Kate are on a level pegging. He was senior to her before, but that’s all going to change. They’ve always been there for each other at the big moments, but there is definitely a rivalry during the day-to-day stuff.”
That “day-to-day” business has included uncovering one of their own anti-corruption unit as a master informer ‘The Caddy’, Arnott being investigated himself, and facing the disapproval of his boss Superintendent Hastings (the wonderful Adrian Dunbar) when he crossed the professional line with a former investigation subject, Lindsay Denton (Keeley Hawes). What will they have to face this time?
“This series will be focusing on forensics and dealing with a whistleblower,” says Martin, being very careful not to give too much away.
“There’ll be the usual twists and turns, and a couple of the interview scenes for which we have become known. Fans have come to expect those scenes, so we don’t want to let them down.”
How does this series antagonist, DCI Roz Huntley, compare with previous Nemeses?
“Well, I loved Daniel Mays as Danny Waldron, and Lindsay Denton outfoxed us twice, so she’s set a high bar, but we do have another good one this time. Thandie Newton is a worthwhile adversary.”
Despite there being no actual AC-12 in real life, contrary to what many viewers believe, Jed Mercurio’s attention to detail has meant many police officers watch the show with great interest. Martin believes it’s a pretty balanced view of the force on show.
“We’re the anti-corruption squad, so there’s always going to be the bad apples on show. But for every bad one, there’s a good one, and at the top of the pile is our own Lieutenant Hastings. He’s a trooper.
“I like to think the show reflects real life. We’ve explored a terrorist threat, and there was historic child abuse in the last series, so we’re pretty married to the times. We show the best and worst of it all, taken to a dramatic extreme.
“What I like best about our show is that there aren’t really maverick cops going out on a limb the way you get in other dramas. Our drama is in the day-to-day, the proper minutiae, the forms you have to fill in to sign out a weapon, all that kind of stuff. I hope viewers like seeing the small detail. I know I do.”
Martin was originally discovered by director Ken Loach in his native Glasgow, and one of his great achievements in this show is hiding all trace of his Scottish accent. How does he do it, particularly when the page-heavy interrogation scenes come his way?
“It’s like a muscle you work, like going to the gym,” he explains. “We have these long interrogation scenes, I can’t be worrying about my accent, it has to be tuned.”
Martin uses the time between series to explore other projects and says, with a series of the quality of ‘Line of Duty’, he says he’s not afraid of typecasting.
“It’s been a great time in my life, not just appearing in the show, but also hanging out with these people for months of the year.
“It always comes as a shock at the end of filming when we go our separate ways. Plus we get big breaks in between, so it’s not all-consuming.”
How many more series can we hope for?
“As long as Jed is happy to write, I’m there for him. With this show, you never can tell how long your character is going to be around, but I’m there for the long haul.”
‘Line of Duty’ Series 4 begins on Sunday evening on BBC One at 9pm.