"Borgen" is back. The Danish political drama about a charismatic woman who becomes prime minister took the world by storm and morphed into one of Scandinavia's biggest television exports returns a decade on.

On Sunday, the fourth series will air on Danish TV ahead of its much-anticipated international debut on Netflix in the spring.

Viewers last saw former Danish prime minister Birgitte Nyborg the day after her brand-new political party scored a sensational win in elections. Ten years on, she is foreign minister in a government headed by a woman 10 years her junior.

"Since we said goodbye to Birgitte, a lot of things have changed," said Henriette Marienlund, head of drama at Danish public broadcaster DR which developed the series.

"She's older, her life is different, her children have grown up and the world is different," Marienlund told AFP.

As Denmark's top diplomat -- a job she was eyeing at the end of season three -- Nyborg now finds herself dealing with the discovery of oil in Greenland, Denmark's autonomous territory, believing it holds the key to its independence.

For the fourth season, "Borgen –- The Kingdom, the Power and the Glory", series creator Adam Price wanted a whole new storyline, explained Marienlund. Many of the original actors are back, however, including Sidse Babett Knudsen as Nyborg.

Except this time, she has a very different role.

Denmark's new fictional prime minister, Signe Kragh, has no intention of getting her toes stepped on, and the same goes for Greenland's foreign minister Hans Eliassen.

'More international'

"Even though this season is more international than the previous ones, it is still a very Danish series where you see a lot of the Danish lifestyle", said Marienlund.

It was this skilful mix of "hygge", the cosy Danish outlook seen as exotic abroad, with realism, as normal people grapple with everyday problems that was considered integral to its success.

"Borgen was commissioned for a Danish audience", says University of Copenhagen assistant film professor Eva Redvall, an expert on Scandinavian drama.

"Its international success came as a surprise," she added.

"The interplay of the political arena, the personal drama and the media in a Danish setting turned out to also intrigue and fascinate abroad".

When "Borgen" first aired in 2010, its portrayal of a woman running a government as well as raising two young children was relatively novel, at least in many Western countries. It was not until 2011 that a woman first served as Denmark's prime minister as reality followed fiction.

In the intervening years, a woman became Sweden's prime minister in 2021. Britain got only its second in 2016 and in 2017, Jacinda Ardern became New Zealand's first prime minister to give birth while in office.

"In Denmark, Borgen is mainstream TV and abroad it's a niche subtitled series. The international audience sometimes focuses on things that are not subjects to talk about in Denmark, for instance the prime minister biking to work", adds Redvall.

Popularity of Scandi drama

Sold to more than 190 countries, "Borgen" gained a new and younger audience after its first three seasons landed on streaming site Netflix in 2020.

The site has invested heavily in Scandinavian productions.

By end-2021, Netflix's overall catalogue included more than 70 Nordic shows, illustrating a seemingly insatiable appetite 15 years after popular gritty Danish crime thriller "The Killing" first aired.

"What started with 'Wallander', 'The Killing', 'Borgen' and 'The Bridge' has developed into more varieties and genres'," from the rom-com 'Home for Christmas' to science-fiction series 'Real Humans', Redvall says.

Netflix "has helped promote that diversity because they have made more people watch series with subtitles, which was very uncommon before, especially for UK audiences".

According to the streaming site, almost two-thirds of subscribers worldwide watched a Nordic series or film in 2021.

Netflix hasn't revealed a release date for the eight new episodes of "Borgen" yet, but it won't be until after the series finishes airing in Denmark.

In the country of 5.8 million people, previous seasons attracted up to 1.6 million viewers.

"There's a lot of hype, so many people will probably be watching", says Redvall, "especially since there is a combination of 'old' viewers and a new younger audience who discovered the series on Netflix".

For now, only one new season has been filmed. Its budget hasn't been disclosed.

"I don't know yet if there will be more", says Marienlund, nevertheless hoping for a hit.