The Killing 2: interview with Sofie Gråbøl

Earlier this year, Sofie Gråbøl was rehearsing for a stage version of Ingmar Bergman's Fanny & Alexander in Copenhagen when a call came from the BBC. They were showing a series she had done for Danish television five years before, and wanted her to come to London to do some interviews. She was too busy, she replied, but when she expressed surprise that there was such interest in Forbrydelsen in Britain, they told her to Google its English title, The Killing. She was astonished at what she found online: blogs, chat-rooms and long discussions about every detail of each episode shown (even obsessing over the jumper her character wore), which had started on BBC4 with very little fanfare, but developed an almost cult-like following. 'I couldn't believe it!'

Gråbøl stars as Sarah Lund, a taciturn detective who is about to give up her job in Copenhagen to move in with her boyfriend in Sweden when a 19-year-old girl, Nana Birk Larsen, is found murdered. Each hour-long episode of the 20-part series represents a day in the subsequent investigation, which quickly involves politicians battling for the post of city mayor, teachers and students at Nana's school, and even throws suspicion on some of Lund's fellow officers.

But if it's the whodunnit that keeps you gripped, it's how the story is told that makes it some of the best TV in years, right up there with The Sopranos, The Wire and Mad Men (with more than 500,000 viewers, The Killing actually drew in a bigger audience than the first British showings of Mad Men). 'It's proved that television audiences aren't stupid and you don't have to serve them fast food all the time: a lot of easily digested action, sex scenes and car chases,' Gråbøl says. 'They actually want a slower pace where you can get more nuanced about the characters.'

The Killing wasn't just a crime thriller, it was about the consequences of murder. We see the quiet, utterly convincing grief that gradually unravels the Larsen family, and how the crime and its media coverage affects local politics. We watch Lund's own life fall apart because of her single-minded pursuit of the truth, and become familiar with the guttural rhythms of the Danish language – like German, with all the rough edges washed away. If you haven't yet seen it, it's out on DVD: treat yourself, before the second series (made in 2009) starts on BBC4 in November.

When it was shown in Denmark in 2007, the series was an instant hit, with more than half the country's population tuning in to find out who killed Nana. Since then it has taken on a life of its own, being shown across Europe at different times. So Gråbøl is now working on a third series, while still promoting the earlier two. 'The odd thing for me is, I'm on a new case now,' she says. 'British people are very much into the first story, but I can't remember it that well because it was years ago.'

It is a gloriously sunny October day when we meet, and Copenhagen is virtually unrecognisable as the murky, rain-soaked setting of The Killing. Full of great coffee shops, waterways and green open spaces, it is an attractive city. Gråbøl has lived here all her life, and has a flat in the very centre, by the picturesque Nyhavn area. 'I sometimes dream about a house and a garden for my kids, but I love Copenhagen. It's small for a capital, so it's not that noisy and dirty.'

One of the odd side-effects of The Killing's success has been an increase in British visitors to the city, and there is now a walking tour to some of the settings. 'What are they going to see?' Gråbøl ponders. 'I guess the main thing is the City Hall. And the police headquarters is a beautiful building. But would you go on a tour like that? No.'

Both her parents were architects, and Gråbøl began acting almost by accident. 'I had just finished school, and I didn't have any ambitions or plans for the future. There was an ad in the paper saying they were looking for a young girl for a film about Paul Gauguin [The Wolf at the Door, with Donald Sutherland playing the French painter], and I just stepped into it. I thought it would be like a summer holiday job. But I felt at home in the language of acting. Then one film led to another and suddenly I was an actor and I never really felt that I had made the decision.'

Sofie Gråbøl has been famous in Denmark since making her debut at 17, with three films in one year, so The Killing has not changed her life particularly – though making it has been a happy experience. 'There was such a great chemistry from the beginning, and that has lasted. It's brilliant writing.'

She had previously worked with The Killing writer Søren Sveistrup in 2002-3, on an Emmy award-winning romantic comedy series, Nikolaj and Julie. He is, she says, confident enough to invite input from his cast, and Lund's character grew out of their discussions. Gråbøl spent a few days with a female detective in Copenhagen's homicide squad to research it.

'I had so many clichés in my head from TV and films.' What she discovered, she says, was predictably banal. 'Funnily enough, the police department is actually made up of regular people. But the woman I met didn't fit in with the images that I had of female detectives, and that was very liberating.'

She also had to take shooting lessons, which she didn't enjoy as much as she thought she would. 'I didn't like holding that gun. There is a feeling of extreme power in it: in a split second you could actually kill someone. And I wasn't good at it at all. There's a close-up of me in season one where I'm in the apartment of a blind woman, and I thought, "This is the Ninja shot!" But then afterwards I saw that I was holding the gun with three or four fingers inside the trigger part!'

Gråbøl enjoys her creative relationship with Sveistrup. 'We don't fight, but there are sometimes very animated discussions. We make each other better. Also he writes as you shoot, which is unheard of here. It's expensive, because there's no time to plan: you book locations that you end up not using, and everybody has to be flexible.

'It's so brave of him to work that way. It's like he's laying down tracks with a train moving towards him. Such pressure! We get the script on Friday and we start shooting Monday, and even then it's not really finished. Last week we were shooting at night and every scene was rewritten, so you're learning your lines in the make-up room.'

In the second series, the only familiar characters are Lund and her boss, Brix, and her investigations take her into the military, and an incident with Danish soldiers in Afghanistan. You miss the old characters at first, especially the charismatic mayoral candidate Troels Hartmann, but he is replaced by an equally likeable justice minister, struggling to keep on top of his new job while dealing with a series of murders that may also be acts of terrorism.

'It's very different. In the first season there was always this very human element, like the grief of the family, you always felt a heart. In the second season, the writer took everything into darkness, and the plot is much more complicated. And my character – I think we wanted to find out how far into darkness we could take her.'

At that point I ask about the jumper, and Gråbøl rolls her eyes. The thick, shape-concealing snowflake-pattern sweater worn by Lund throughout the first series was her idea. She remembers her hippie parents wearing similar ones when she was a child: it would show Lund's lack of interest in being seen as a sexual being, while also hinting at a desire for homely comforts and intimacy that she has no idea how to obtain. That's a lot of subtext for knitwear, but viewers got it. And then they wanted one of their own.

Gudrun & Gudrun, the Faroe Islands company that hand-knits the €280 sweater, found it hard to keep up with demand when the series was on Danish television. The rest of Europe failed to get as excited, but since The Killing came to British screens, it has again been swamped with orders.

In Denmark, Gråbøl says, other shops began selling their own, cheaper copies. 'The company went bonkers.' She thought it was an overreaction, until she learnt what the patterns mean. Faroe Islanders have relied on fishing for generations, and each family has its own unique design. 'So if there was a storm, the women could stand on the shore and from a great distance they could see if their husbands, sons or other family members were still on board. So of course they have emotions connected to those patterns. It's not just a designer cooking up something. It has roots.'

But when the second season of The Killing was announced, she got tired of being asked if the jumper would also be returning. 'It pissed me off because I thought, "Who cares whether I wear that stupid jumper! Why don't you ask what we're going to do with the character?" So we all agreed that we weren't going to give them the jumper. We were almost jealous of it getting all the attention.'

At the start of season two, Lund is wearing a more fitted red sweater (already for sale on Gudrun & Gudrun's website, for €240), but fans of the original, seemingly indestructible design can rest easy. 'After five or six episodes, I went to the producer and said, "I hate to say this, but I need the jumper back." I really missed it.'

With her hair scraped back into a ponytail, her face free of make-up and the sweater worn with jeans and flat shoes, Lund is an attractive woman, but one who clearly doesn't care about pleasing other people, or using her sexuality to get the job done. When I comment on this, Gråbøl laughs and says that several Brits now have told her that one of the things they love about The Killing is that she's not beautiful. She takes it as a compliment. 'I know what they mean. We're real people.'

Surprisingly, so far she has had no offers of work from Britain, except for a brief guest appearance in a new episode of Absolutely Fabulous. 'I'd love to go and work in Britain, it would be a challenge. I've been acting since I was 17 and I'm 43 now, so people in Denmark have known me for a long time. But in Britain I'm just this mysterious strong, fascinating character, Sarah Lund.'

Currently she is three episodes into the third series, and although it will be shorter – only 10 hours – she says Sveistrup will once again entertain, while touching on bigger issues. 'In the second season he deals with the dilemmas of war, what war does to people, and what power does to politicians. In this third season he is dealing with the financial crisis, which is a pretty big topic as well.'

Like the other two series, it takes place in November. 'By then in Copenhagen, it's dark at 5pm. So even if they write a scene that takes place at 6pm, you have to shoot at night. I find that very hard, turning your hours around.'

Gråbøle has two children, a son aged 10 and a seven-year-old daughter. She is divorced from their father, and says the irregular schedule plays havoc with her childcare arrangements. 'Because there aren't any scripts, often I don't know when I'm going to shoot in the next week. Forget the murder case: the real drama is finding a babysitter. But I have a great relationship with my ex, so when I'm under pressure for time, he takes them, and when he's under pressure I have them with me.'

Her children have never seen her on television, or in film. 'Ever since they got old enough to watch more adult drama, I've been doing The Killing, which isn't suitable. Then I played Lady Macbeth, and that wasn't really for them either. The first time they ever saw me act was when I did Fanny & Alexander. I was extremely nervous, more than on any opening night, because my character has a son and a daughter the same age as my kids. I thought it might be weird for them to watch me up there having other children, kissing other men and crying. But they were totally cool about it.'

She is single at the moment, she says, because the combination of young children and intensive shooting does not leave a great deal of time for a social life. Today is a rare day off, and after our meeting she is going to pick up her children and two of their friends, then build an Ikea desk for her daughter. She likes doing things for herself, and doesn't have a nanny, a cleaner – or even an agent.

I ask if she can envisage a fourth series of The Killing, and she says no. 'But I still love doing it. I've been in plays where after 10 performances you're thinking, "When will this ever end? I'm finished with it!" But I'm never finished with this project. It keeps fascinating me. The character is so remote from me, and I like that. It's like having this parallel life going on.'

'The Killing 2' starts on BBC4 in late November