ALYSSA Sutherland can't seem to get away from her on-screen husband.
The Brisbane-born model plays Princess Aslaug in the award-winning drama Vikings opposite fellow Aussie Travis Fimmel, who stars as central character and Norse legend Ragnar Lothbrok.
The Canadian-Irish production set in the Dark Ages continues to gain popularity, with an additional 10 episodes (20 in total) added to the upcoming fourth season debuting on SBS on Wednesday.
"Everywhere I look people have a Ragnar haircut. It's so funny and so cool as well." Sutherland laughs.
"It seemed to happen overnight somewhere between filming seasons two and three. All of a sudden there were so many people who were aware of it.
"I'm so lucky for my first big role I've had that I get to be on a show that's respected and growing season after season. I don't think that's common when you start out."
Fimmel, also a former model, brings a dangerous intensity and intelligence to the famed warrior and king of Denmark.
Sutherland says her co-star keeps everyone on their toes.
"The cool part of working with Travis is you never really know what to expect," she says.
"I really like that. He'll throw out a curve ball in the middle of the scene and if you've got the guts to go along with him and stay in the moment and be present then it always works out.
"It's wonderful to work with someone fearless like that."
But with Ragnar on his deathbed after the sacking of Paris, Aslaug has her eyes on the throne in the premiere of season four.
"Their relationship is incredibly intense but it's not the most loving of relationships," she says.
"At the end of season three you see her take more charge and it carries on from there in season four.
"The question up in the air is what will happen to Ragnar. He's not well and in the event of his death who will be running the town? At the start in season four there's this interesting subtext between Aslaug and (Ragnar's eldest son) Bjorn.
"She wants to rule in her own right."
But with 20 episodes to air in two parts this year, Sutherland says anything could happen.
"A lot does happen and I wish I could tell you what's going on," she says.
"There's stuff people will be absolutely shocked by. It's just as exciting for us as we only get the episodes (scripts) a week or two before we film them."
New characters introduced this year include King Harold Finehair (Peter Franzen) and his chaotic younger brother Halfdan the Black (Jasper Paakkonen) and Chinese slave Yidu (Dianne Doan).
Vikings season four debuts on Wednesday at 8.30pm on SBS 1.
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