‘“Mad” Frankie Fraser told me how to get someone to talk’: how we made The Shadow Line

Hugo Blick, writer, producer, director

I’d been making comedy for a decade and had a breakout success with Marion and Geoff. In 2010, I decided to swing my bat and write my first drama. I went from writing about one guy in a car to a noir thriller on an ambitious scale. It utterly transformed my career.

The title wasn’t a reference to Joseph Conrad’s novel; it was about moral ambivalence. The Shadow Line was a story about two men, Christopher Eccleston’s organised criminal and Chiwetel Ejiofor’s amnesiac cop, working on either side of the line. The sort of people who, in thrillers, tend to get themselves killed. Only the ones who can walk the line survive, like Stephen Rea’s character Gatehouse – the true kingpin of the story.

Chris’s character tells Rafe Spall’s: “You’re too loud. We’re not supposed to be heard. Ever.” That’s the great criminal mindset – you operate in the shadows, committing unseen crimes. You never hear about the real bad guys until they’re pulled into the light and exposed. Chris smuggles drugs through his florist business. There was a real-life Flowers Gang but that emerged afterwards. Someone suggested they’d used The Shadow Line as inspiration. I said: “I hope not. They got caught!”

I never had to do much research when I was writing comedy, but suddenly I did, and I found it fascinating. I met all sorts. “Mad” Frankie Fraser told me: “If you need a guy to talk, Hugo, take a Phillips screwdriver and insert it in his ear canal. He’ll tell you anything.” South London criminals have this mordant humour which I tried to reflect in the scripts. There’s a baroque quality to the dialogue. It isn’t realistic but it feels true. Visually, I wanted a monochromatic tone – all contrasts and verticals, like the top lighting in The Godfather. Black and white with flashes of red, from tomatoes or blood.

I love 70s conspiracy thrillers such as The Parallax View and All the President’s Men. There’s a lot of Max von Sydow’s assassin from Three Days of the Condor in Gatehouse but his dry, desiccated voice was Stephen’s idea. There is also a bit of Sidney Poitier in Chiwetel’s role, right down to the Mister Tibbs tailoring. Rafe made a terrifying psychopath. The scene where he almost drowns a cat held the record for most complaints for a while but it still makes me laugh. There’s a joyful nastiness in The Shadow Line but, I hope, humanity, too.

We shot mainly on the Isle of Man because of the tax breaks. There isn’t a part of its underground car parks I didn’t use. Just out of frame would be a lift up to Marks & Spencer. The island is often shrouded in gloomy mist, which was brilliantly atmospheric. We even found a hillside sheep-pen in the shape of cross-hairs for the climactic shootout.

Stylistically, I’m aware mine is a Marmite approach. When it first aired, The Shadow Line got a kicking from critics who found it confusing, but to me, it’s straightforward. I plotted it all out on a whiteboard, working backwards. I once saw a meme where Gatehouse and Anton Chigurh from No Country for Old Men face off. I tell you, Gatehouse would win.

Stephen Rea, played Gatehouse

Hugo’s scripts were so astonishing, I said yes straight away. He had thought there might be an IRA element to Gatehouse but I didn’t see it. It was more about political manoeuvrings. My big secret was that I got his voice from Harold Pinter, who I’d worked with a few times – it was my way of guaranteeing an accurate English accent. Pinter’s voice had terrific authority and something official about it. Gatehouse’s version felt affected – a choice rather than a voice – which somehow made it more sinister. Maybe underneath, he was Irish after all.

His look – hat, glasses, gloves, overcoat – was all down to Hugo. It would have made a good Halloween costume. I’ve played a lot of vulnerable, troubled roles but Gatehouse was focused and horrible, killing without thought. He walked into a house and knocked off an entire family. Obscene. One morning, I met Eve Best for the first time. Within 20 minutes, I was killing her. In another scene, Gatehouse used a baby monitor to terrify a mother. As he left, he said, “I’ll see myself out,” which was somehow very funny.

He made a big impression because he was so irredeemably unpleasant. Hugo said he was like an old uncle – you don’t take much notice of him until he’s got a piano wire around your neck. I couldn’t follow the story half of the time but often, in murder mysteries, you can’t unravel all the threads. Nobody knows who killed the chauffeur in The Big Sleep. But Hugo knew what he was doing all right.

It’s one of the most memorable things I’ve ever done, thanks to Hugo’s gloriously twisted mind. I’ve made three dramas with him now: The Honourable Woman and The English, too. I’d drop everything to work with him again.

• The Shadow Line is available to rent on Apple TV+ and Amazon Prime Video.