Noomi Rapace got her first sliver of a film role in Iceland, where she lived for three years as a young child. Her stepfather was looking after the horses for a medieval spectacular called Shadow of the Raven and she had tagged along to the set. Before she knew it, she was on camera dressed as a Viking.

“It was a very small part,” she laughs. “But it changed my life. I think I discovered that you can have fun as an adult, because I saw all the actors go in every day with so much bravery and concentration. It was a really brutal story – I saw a lot of deaths -and really romantic, like Tristan and Isolde. I was standing there entranced, thinking ‘I never want to leave this universe’.” Noomi Rapace: ‘Iceland always had this effect on me: it feels like I’m looking at myself’ A year later, the family returned to Sweden. Noomi went to acting school and was eventually catapulted to world renown as Lisbeth Salander in the Swedish film adaptation of The Girl with the Dragon Tattoo and its two sequels. Now 41, she recently returned to Iceland to star in the stunning Lamb, which won a prize at the recent Cannes Film Festival for originality.

It is the story of a farming couple conjoined in grief following the death of their only child. Then an extraordinary event gives them the chance to be parents again, Rapace plays Maria – strong, capable, stoic – whom she describes as a mix of herself and her Icelandic grandmother. They shot in an abandoned farmhouse; a skeleton cast and crew of 30 lived and worked there, accompanied by a flock of sheep and a cat. There was no phone signal. “Which totally isolated us,” she says. “You stop thinking. It becomes quite primitive. I became a creature in the animal kingdom more than a human in civilisation.” Lamb was directed by Valdimar Johannsson, who wrote his weird, mythic story before asking much-garlanded novelist Sjon Sigurdsson to help develop a script. For years, the two of them met twice a week to talk about Icelandic folk tales and go to the movies.

“For me, this is a classical story,” Johannsson says, “I know everyone is talking about it as genre or horror, but we just wanted to make an arthouse film.” It is also peppered with that sideways Scandi humour that pulls sudden laughs from anywhere, even a sheepshed. Both Johannsson and Rapace grew up on farms. “It’s not so far-fetched for me to go into something really practical,” Rapace says. Delivering new lambs was something new, however. “I was waiting in my trailer for the knock and then it came – there’s a lamb coming – and I was running down rolling up my sleeves and then down on my knees, my hands there pulling out something I had never seen before. I will never forget the lamb when he opened his eyes for the first time and took his first breath. It was life, but it was also so fragile. And that is us.”

She delivered seven in the end. Their owner even offered her a job. “So you know, if this doesn’t work out…” she laughs. Rapace only lived in Iceland between the ages of five and eight, but she went back on summer holidays to help in her grandparents’ commercial greenhouses and with their horses. She speaks Icelandic like a native. “I think with this movie, why it became so extremely special to me is because this is where I found my voice. When I was a kid. When I first came to Iceland I felt I didn’t belong to anything and that was my first sense of belonging.”

Merging with her character, she felt she was healing along with her. “I felt like Iceland always had this effect on me: it feels like I’m looking at myself and there is nowhere to hide. It’s just me, with all my shit and all my demons and all my good sides and you can’t avoid any of it. So you get like forced to tell the truth. And I felt when I came back to Iceland, this is where I want to be.” It is now two years since they made Lamb and Noomi Rapace is busier than ever, with five more titles racked up; when we meet she is shooting Django, a spaghetti western series for television. There is still one more Lisbeth Salander novel that hasn’t been filmed in Swedish, but she won’t go back. “All my characters live in me, like former partners. But they’re in my memory lane, my inner library.” But could Maria return for a Lamb sequel? In Iceland, apparently, anything is possible.

Lamb is showing now in selected cinemas