Welcome to Straight to Series, where Backstage takes a deep dive into how some of our era’s most celebrated TV shows got made – and how you can make one.
Line of Duty, now finishing its sixth series on the BBC, is a fiendishly complicated police procedural following the work of AC-12, a fictional anti-corruption unit determined to root out ‘bent coppers,’ whatever it takes. Led by Superintendent Ted Hastings, played by Adrian ‘Adey’ Dunbar, AC-12 investigates police corruption and possible links to an organised crime group – or OCG. He’s ably assisted by Detective Inspector Kate Fleming (Vicky McClure) and Detective Inspector Steve Arnott (Martin Compston), and this terrific trio stops at nothing to bring the criminals to justice.
Line of Duty is a ratings juggernaut for BBC One – 11 million people tuned in for the penultimate episode of Series 6. The show began back in 2012 on BBC Two, making an immediate splash by becoming the channel’s best-performing drama series in 10 years. Since then, it’s also made the leap to Netflix, earning it even more viewers globally.
Line of Duty was created by writer Jed Mercurio. A former junior doctor and Royal Air Force officer, Mercurio is now one of the UK’s most successful TV writers and showrunners, responsible for hit shows such as Bodyguard, Cardiac Arrest, and Frankenstein. He drew inspiration for AC-12 from the real-life Met Police anti-corruption unit AC-10, though famously, the real police refused to cooperate (officially, at least) with Line of Duty’s makers.
Mercurio’s relationship with the BBC goes back to the 1990s, when World Productions made Mercurio’s writing debut Cardiac Arrest for BBC One. Other collaborations followed, including Bodies – ranked by The Guardian as one of the “Greatest TV Dramas of All Time.” So, it wouldn’t have been too difficult to set up a meeting to pitch the concept for Line of Duty.
Yet when Mercurio, together with executive producer Simon Heath and World Productions first approached the BBC with the idea, it was far from an immediate green light.
“The pitch very much landed that it was cops versus cops, and that’s what set it apart from other things on the commissioning slate.”
Speaking to GQ, Mercurio described the pitch: “We just talked about doing a cop show that felt fresh, and one of the things that we had noticed from the start of the 21st century was they had been very formulaic; they’d been diligent, well-meaning cops catching the bad guys and there hadn’t been a British cop show that delved into the dark side of policing or the darker side of the police as an institution. The pitch very much landed that it was cops versus cops, and that’s what set it apart from other things on the commissioning slate.”
Executive producer Heath takes up the story: “Initially, we were turned down by BBC One. Perhaps BBC One was a more conventional channel and wasn’t prepared to take the risk of dealing with a programme that followed corrupt police instead of heroic police. That looked a bit fatal at the time because this was an era when drama had slightly disappeared off BBC Two.”
Luckily for the show’s subsequent legions of fans, and unknown by Heath and Mercurio at the time, the then-controller of drama at the BBC, Ben Stephenson, had managed to secure a life-line, clawing back some of BBC Two’s drama budget.
Heath says: “He had quietly earmarked Line Of Duty as a show that he wanted to see leading the charge on a revamped drama slate. But from that turn-down to getting the green light was another nine months, and we’d already been waiting about six months before that, so it was an extended period of time and I’d be lying if I said we were all certain that we would get the green light.”
Talking to The Big Issue, Mercurio summed up the BBC’s expectations of the show back in 2012: “It’s brilliant that the series has become so popular over the years. We started as a pretty small drama on BBC Two – a summer schedule filler in 2012 when it was crammed with the Olympics, the Euros and Wimbledon.” Nine years and 11 million viewers later, Line of Duty is now one of the BBC’s biggest and most loved shows.
Showrunner Mercurio said to GQ: “I think you have to approach the casting in a way that allows the actor to embody the role and to fire your imagination as a writer.”
Kate Rhodes-James is the casting director on Line of Duty, and Craig Parkinson, who plays DI Matthew Cottan on the show, is clear the production owes her a lot, telling The Big Issue: “She’s the one that’s coming up with all these ideas. Right from the start, we all came from an independent film background – I’d done two films with Martin Compston; Vicky McClure was coming off the back of Shane Meadows’ This Is England; Lennie James and Gina McKee were highly respected actors but not from mainstream television. The most high-profile person was Neil Morrissey – and who else would have thought to put Neil Morrissey in that part?”
Mercurio expands on this: “Good actors will tell you things that help you write. Adrian came in very early, and the character was conceived very differently from how Adrian did it, and we brought that in and it changed the dynamic. And really the same was true of all the cast. I had no preconceptions.”
Martin Compston, who plays Detective Inspector Steve Arnott on the show, describes to Backstage how he approaches his character: “I saw that Steve loves his job but he’s arrogant, pigheaded. There’re times he thinks he’s the only one doing the right thing. His doggedness is an asset but it can rub people up the wrong way, and he has this ridiculous way with women that nobody can quite understand, not even me. The cockiness that comes with that is one of the reasons I put him in waistcoats. In my head, he’s the guy who works in a call centre but is overdressed, is having office affairs. There was also a nod with the waistcoats, as all the great detectives have them, from Sherlock onwards.”
Vicky McClure – Line of Duty’s DCI Kate Fleming – said: “I remember my audition being a shocker. I hadn’t learned my lines. Some people they’re so prepped and I just wasn’t. I missed my mouth when I went to have a drink of water and it all went down my top. I thought, ‘There’s just no chance I’ve got this, to be a cop, I can’t even learn the lines.’ I remember feeling quite underprepared.”
One of the show’s signature features is how it attracts top talent to take a central role usually for one series only. Kelly Macdonald, Keeley Hawes, Lennie James, Thandiwe Newton, Stephen Graham and – briefly – Daniel Mayes have all guest-starred on the show. Other notable actors such as the brilliant Anna Maxwell Martin, James Nesbitt, Polly Walker and Gina McKee have all come and usually gone again relatively quickly – all keen to be part of the Line of Duty Universe.
When it comes to production, Mercurio remains very hands-on. He told the Royal Television Society: “I think it’s odd that some writers don’t want to be on set. If you’ve written something, you have a vision about how it’s going to be realised and you can be of help to people who are taking that vision on. Even if it’s just being able to clarify what a line means or what an important point is in a scene, that’s so valuable to the production.”
“The more film-friendly your writing is, the more your scripts will appeal to people.”
“I understand how something has to be filmed and that informs my approach to the writing. The fact is, you can imagine whatever you want, but if you want someone to perform and film it, it has to be physically possible within a timeframe and budget. As you gain experience, you start thinking more about that. The more film-friendly your writing is, the more your scripts will appeal to people.”
One of the joys – and frustrations – of Line of Duty is its exceptionally complicated plots. Storylines such as the identity of mysterious bad cop ‘H’ spread over many series and viewers are expected to remember plot points and characters from years ago. On top of that, audiences also need to understand the show’s liberal use of police acronyms and terminology. If you don’t know the difference between your ADOs, UCOs or CHIS then you’re clearly not sucking diesel, fella.
It’s not just audiences who can be intimidated by the lingo. Kelly Macdonald told the Radio Times she nearly turned down the role of DCI Joanne Davidson because of the sheer amount of words she’d have to learn: “When I saw the script, my first instinct was to run a mile. It’s all addresses and dates and police jargon, especially when I was interviewing suspects.”
Craig Parkinson described to us the benefits of having no idea upfront about his character’s arc and who he would become: “It’s a gift as an actor not to know. Had I been pulled aside and been told I was this mastermind I might have played that and given something away. It would have been terrible.”
A signature characteristic of Line of Duty is the show’s willingness to shock. Cliffhangers, good characters turning out to be bent, and the joyful disposal of its big names if the plot demands it all mark the show out. Martin Compston told Backstage that back in Series 4 when his character Steve Arnott was thrown over the stairs, he wasn’t sure of the outcome: “I didn’t know how viewers would react. I thought people might want my character to die, but Jed said: ‘Wait and see the reaction – people don’t know what they’ve got until it’s gone.’ And there really was an outpouring of love for Steve that changed my relationship to him and with the audience. That’s the genius of Jed.”
A notable feature of the ensemble cast and production team is that they genuinely seem to get on, reflected in the number of times they refer to and compliment each other in interviews; and it’s likely this is both down to skilful casting and to mindful management.
The central trio of Compston, McClure and Dunbar regularly share their behind-the-scenes antics, whether larking around on set or inadvisable TikTok dances. And when they’re filming in Belfast, the team all live in the same block of flats and go for a curry at least once a week. This camaraderie continued throughout lockdown – Martin Compston told BBC Radio 1 that he, McClure, Dunbar and Mercurio hook up on zoom every Friday night “for a few wines” to talk over fan theories and discuss how the show’s been going.
Although it’s set in an unnamed central police force, Line of Duty is actually filmed in Belfast, where the cast all relocate during shooting. The city’s BT Riverside Tower is AC-12’s Belfast home and the city’s Central Library serves as the series’ Police HQ.
Like everything else in the world, the filming of Series 6 was interrupted by Coronavirus, but after an unscheduled production break, shooting eventually wrapped in November 2020.
One of Line of Duty’s signature scenes is the long, acronym-heavy interrogation scenes filmed in AC-12’s offices. All the guest stars end up in that glass box eventually, and the grilling of Series 6 star Kelly Macdonald recently lasted 30 minutes on screen, with the first 10 minutes consisted of her answering “No Comment” to almost every question.
Unlike most TV drama, these scenes are filmed in a single take and have been compared by the actors to mini-plays. Compston described his mixed feelings about them to the Guardian: “They’re both an actor’s dream and nightmare. When you get the script, you faintly hope you’re not in them, but then if you’re not, you’re devastated. It’s the boom guys I really feel sorry for – you can see their arms shaking. It’s a tough day’s work. We’ve got a couple of pretty epic ones this series.”
McClure agrees, revealing to GQ: “It’s a painful process of learning it. Because there is only one way of learning lines, there is no cheat, you just have to repeat, repeat, repeat. When you’re in there and you’ve just done a full take, you’re ready to go again. And you’ve got beats in there that you just wouldn’t get if you were cutting the camera. And it is tense and you’ve sat there so many times thinking, “I do not know my next line and I do not want to be the person 25 minutes in to fuck it up.” And then all of a sudden it just comes to you, because the writing is so solid. Jed just takes it out of the bag every time and they’ve become iconic scenes for our show.”
And on the topic of learning lines, it comes as a surprise to many that Compston’s native accent is Scottish. He reveals his struggle with it to The Times: “That dialogue on its own would be hard anyway. Throw the accent in there... the scene we did the other night, a 30-pager, trying to juggle the accent at the same time. When I do that voice I can hear him, it’s like a costume.”
He gets an Englishman to record the lines for him so he can practise. “I walk about all day with him in my ears. It’s just graft. I’m not naturally good at accents. I need to work harder, which then makes me better because I’m not complacent with it.”
Series 7 is yet to be commissioned by the BBC, and the Times reports Compston as hinting that Series 6 may be the last, as it ties up plot strands that have been trailed since the first series in 2012. Yet the main cast members have said they’d like to do more, and Mercurio told the Royal Television Society: “None of the series I’ve worked on have come to an end because any of the creative people didn’t want to continue. It’s always been a decision that has come from the broadcaster and almost always because of a change of personnel.” And perhaps teasingly, he suggests the end may not yet have been arrived at: “Yes, I do know how Line of Duty will end. I have it planned out as an overview but not the detail yet.”
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