Craig Parkinson on the "gift” that was Line of Duty and his new, challenging role in Killed By My Debt

When the third series aired in 2016, Parkinson’s Caddy was the nastiest man on television, a part the 42-year-old actor describes as a "gift”. Perched on a very large and frumpy armchair in a hotel in Fitzrovia, Parkinson’s face illuminates when he speaks about Line of Duty.

“It meant everything,” he says, explaining that having done the job for so many years, his co-stars Vicky McClure, Adrian Dunbar and Martin Compston “became a family” to him. Was it hard to say goodbye to the show? “I don't think so. It was slightly sad but if [Dot] hadn't been caught then, we would have lost the edge a bit. What Jed has never done with his scripts is patronise the audience. With some other dramas, the audience are two steps ahead of the story, but with Jed's scripts, the story's at least four steps ahead of the audience.”

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• Everything you need to know about BBC3 factual drama Killed by My Debt
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Parkinson was “overjoyed” when he found out Dot was The Caddy – a twist revealed to viewers at the end of series one. “[Roles] like this are a gift and you don't really get things like that often,” he muses.

Did he watch the most recent series of Line of Duty starring Thandie Newton? Yes – but only on DVD. “I don't have a television in my house,” he admits. “Why is that? Because I f***ing love television and I'd have it on all the time.” He previously told The Guardian that he and his wife, the actress Susan Lynch, “were watching some s*** like I’m a Celebrity in our flat in Camden, and realised we hadn’t spoken to each other for ages”, so decided to get rid of the TV once and for all.

Now, Parkinson is portraying another less-than-saintly character in Killed By My Debt – the latest addition to BBC3’s award-winning strand of factual dramas which has included Murdered By My Boyfriend, Murdered By My Father and Murdered For Being Different. This new film tells the true story of Jerome Rogers, a 20-year-old motorbike courier from Croydon who in 2016 took his own life after two unpaid £65 traffic fines escalated to a debt of more than a thousand pounds.

Parkinson plays the bailiff who visited Rogers twice and clamped his bike – the teenager’s only source of income. “We were very careful not to make the character of the bailiff any sort of villain of the piece,” Parkinson explains, “because if you make it about good versus bad in a story like this then Jerome's story becomes resolved. And it's not resolved – this is the tip of the iceberg. The villain of the piece is the system, and not a guy who [like Jerome] is also on a zero hours contract.”

On whether it was difficult to handle the emotions that inevitably come with working on such a film, Parkinson says: "It always changes from job to job, but with something like this, I was able to switch off actually. Even though the story of Jerome weighed heavy on my mind, it just made me angry more than sad, that things like this happen and it ended in such tragedy."

Born in Blackpool, Parkinson’s career – which has also seen him star in Misfits and Indian Summers – all began when a conscientious deputy headmaster at his secondary school wrote a play in an effort to stop him bunking off and coax him back into class. “He was a closet dramatist… and he knew drama was a bit of a thing of mine,” recalls Parkinson, who was about 14 when he starred in the production. “That was the first time [I was on stage], and then you start getting the laughs and you think, ‘Oh, that's quite addictive.’”

Parkinson says his parents were “supportive” without “actively forcing” him to pursue a career in acting. But his real inspiration, he reveals, is rooted in cinema. “It was always films that I was heavily influenced by,” he says, admitting that as a youngster he would often spend whole days at the movies alone, sneaking between screens so he could watch as many as possible. “Still to this day, if it's my birthday, the ideal thing for me is just to be in the cinema all day and go back to back,” he says.

After leaving school at 16, Parkinson went on to train at Blackpool and The Fylde College. “There were certain actors from the north west that I really looked up to and they went there, so I thought, ‘I want to follow in their path, so I'll go there,’” he remembers. “David Thewlis went there, John Simm. I thought, ‘That's the place to be.’

“You have to look for the people who light your fire and who you can relate to. You can go, ‘He's from my area, I've seen him on the television… if they can do it and they're from my area, then why can't I?’ Kids need that influence in their lives wherever you are, if you're in Glasgow or south London, you look at people that you can relate to,” he says.

“Sadly, more and more kids now are watching too much telly and they just want to be ‘famous’… most actors never even think about that, they just want to act. Everything else can be a right pain.”

On screen, Parkinson will next be seen in master-complainer Karl Pilkington’s Sky 1 comedy Sick of It. He’s also part of the starry voice cast for the BBC’s adaptation of Watership Down, which boasts the likes of John Boyega, Olivia Colman and James McAvoy. Parkinson is playing Sainfoin who, he says, is a “rather rotund sergeant” and, much like The Caddy, “you might think he’s one thing in the first couple of episodes but then he turns into something else”.

When he’s not acting, he's hosting The Two Shot Podcast, which has just won in the Best Culture category at the 2018 British Podcast Awards. On it, he sits down with an actor over a nice hot brew and talks about their trade. He’s a natural interviewer, and his guests have included Amanda Abbington, Vicky McClure, Meera Syal and Danny Mays. The chat is refreshingly luvvie-free, and Parkinson’s passion for drama really comes through. “If you get a chance to do what you love then you never work a day in your life," he tells me. "It's clichéd but it's true."

Killed By My Debt is available on BBC3 from 10am on Tuesday 29th May

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