Good news for those mourning Line Of Duty. There’s another series jam packed with outragous plot twists, bent coppers, psycho gang members, murderous back stories, explosions, shootings, substance abuse and a general disregard for human life. It’s Swedish, called The Lawyer and stars Alexander Karim who has the same reputation for phwooooarness in Scandinavia as Idris Elba does here.

As has become HP tradition, we’ll let the man who’s brought the ten-parter to Irish and UK screens, Walter Iuzzolino, do the introductions. “This slick, sharp rollercoaster thriller starts with a daunting flashback; two young children, Frank and his sister Sarah, witness their parents dying in an explosion caused by a car bomb,” he tells us. “No one is charged. Years later, Frank has become an exceptionally talented defence lawyer working in Copenhagen, his star is rising fast. His sister, however, has never got over the trauma. She’s joined the police force and is searching for the culprits. But she’s struggling with drug addiction and her life is a mess until one day somebody talks. Now the brother and sister know who did it, they just have to prove it.”

And that’s where we’ll stop with the spoilers! It wouldn’t raise an eyebrow here nowadays, but in Sweden much was made of Alexander being the first black actor to star in a primetime TV drama.

“It probably sounds strange to you guys but, while you’ll see people from all sorts of different backgrounds in Swedish series, I’m the first lead who happens to be black. I turned down international jobs to do The Lawyer because I really wanted to just kick that door open. There’s always going to be work abroad but you want to be doing what you do at the highest level in your own country. Commercially, The Lawyer was the most-watched show last year in Sweden, and the biggest series ever for the company that made it, Viaplay. It’s worked on every level so, yeah, the door’s been opened.”

Born in Sweden a year after his Ugandan parents were forced to flee Idi Amin’s despotic regime, Alexander was bitten by the acting bug early.

“We grew up just devouring movies,” he reminisces. “I remember aged five seeing Citizen Kane and thinking, ‘Wow!’ We’d watch a classic like Ben Hur or The Commandments followed by Plan Nine From Outer Space or Zoltan Hound Of Dracula, which fall into the so-bad-they’re-good category. Both of my brothers are directors, so it was natural for me to get into that business. I just went the acting route. I went to drama school to get my training, but also worked as a film P.A. going through every single job there is on a set. From writing and editing to photography and sound, I’ve done it all, which has been a really big help in my career because I know how it all bolts together.”

Alexander’s big break came in 2000 when he made the art imitating life short, Limelight, with his elder brother Baker.

“It’s about a guy working in a kitchen who aspires to be an actor. That had a budget of, no lie, about €10 and did really well at film festivals in Scandinavia. That led to us being contacted by Lars von Trier which, as you can imagine, was a massive deal for us both.”

The budget was considerably bigger in 2012 when Alexander made his Hollywood bow alongside Jessica Chastain, James Gandolfini, Joel Edgerton and Chris Pratt in Zero Dark Thirty.

“My part in Zero Dark Thirty was so small it’s ridiculous, but for some reason the director, Kathryn Bigelow, took to me during my week filming in Jordan,” he smiles. “She was like a little kid taking this glorified extra on a tour of these sets, which had cost millions and millions to construct. Kathryn made it feel like we were making a short film. The way she treated me was brilliant.”

Like The Bridge, the Lawyer action flits between Malmo in Sweden and its Danish neighbour across the Øresund Strait, Copenhagen. What are the stereotypical notions the two countries have of each other?

“The nice one is that us Swedes think the Danes are a bit cooler and less uptight than we are,” Alexander proffers. “You know, everyone rides around on a bike, and has a beer with their lunch. The unkind one is that it’s not just the one pint, they keep on drinking! You’ve the two different currencies, which fluctuate so for a while we’ll feel richer than them and then it’s, ‘Oh my god, we’ re poor!’ The sense of superiority keeps flipping over.

“The Øresund Bridge, which has become sort of iconic, only got built in 2000, but when we were living in Helsingborg, just north of Malmo, my mother took the ferry to work in Copenhagen. The two countries are very intertwined like that.”

Alexander kicked open another door last year when he starred in a major Stockholm production of Shakespeare In Love.

“I wanted to get back to theatre and am a Shakespeare nut, so getting to play Will himself on the biggest stage in the country was another gig I had to take,” he concludes. “Again, I was the first black actor to have starred in a Swedish theatre production of that size. I was on stage for three-hours plus with twenty-two other actors, dancing and crying and jumping and fencing and everything. Compared to that being here in Helsinki filming the second series of The Lawyer feels like a holiday!”

• The Lawyer makes its Channel 4 bow at 11pm on June 23 with all episodes available after on the Walter Presents strand of channel4.com