King Ragnar Lothbrok is likely to kill his brother Rollo in season 4.Facebook/Vikings

History Channel's popular drama series, "Vikings", will tell the story of love and betrayal in season 4, which is scheduled to be aired in 2016.

When the legendary Viking Ragnar Lothbrok (Travis Fimmel) returns to power, he finds a new love interest, which will eventually turn out to be a unique relationship.

Sharing details of the new female cast member, Fimmel said that the character will be played by a very talented actress. He even stated that viewers can expect to see a unique relationship between Lothbrok and the lady in fourth season.

Explaining further about the new love interest, creator Michael Hirst said that it is very unexpected. "When I first thought of it, I did check with a historical expert that this was a possible connection," he told Entertainment Weekly.

Although the actor and creator refused to reveal any information about the actress who would be playing the role, it is assumed as Dianne Doan, who will portray Chinese traveller Yidu in the series.

The "Once Upon a Time" actress recently dished out few details about her mysterious character in an interview with International Business Times US Edition. "The people of Kattegat have never seen someone like her, from her looks, to views on the world and beliefs," she said.

The celeb even stated that the same mystery will attract Ragnar towards her character in the fourth season of "Vikings".

Meanwhile, followers of the history drama can also expect to watch challenges faced by Rollo (Clive Standen) while trying to impress Princess Gisela of West Francia (Morgane Polanski) and the French people.

"We're going to see a completely different Rollo, if he's ever going to conquer Paris and conquer the princess. He has to be far more cerebral, he has to be on his A-game all the time, and his attitude to Ragnar has to change. He can't always be in the doldrums of being this second-best brother that's in the shadows," said Clive Standen.

For Ragnar's son Bjorn Ironside (Alexander Ludwig), it is time to take some responsibility and learn to be a good leader.

"This is the season where he's finally come into his own and now it's about Bjorn and learning from his father, but now there's this camaraderie between the two. You really start to see him step up and start running things when his father initially can't. It's a really exciting time for him and also very nerve-racking," IGN quoted Ludwig.

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