"Vikings" season 4 will address various relationship conflicts faced by Ragnar Lothbrok (Travis Fimmel) and his family, including brother Rollo (Clive Standen), wife Aslaug (Alyssa Sutherland) and son Bjorn Ironside (Alexander Ludwig).

Fimmel's character is never good at relationship with women in the history drama series and the upcoming sequel is likely to begin by addressing several problems between him and his wife.

It has already been revealed that Sutherland's character will have a major role to play in the fourth season of "Vikings" and it will focus on her taste for power. "She's had a taste for power while he's been away and when we return in season four, we'll see that she's enjoying that taste," revealed creator Michael Hirst.

The executive producer even teased a unique relationship for the Viking leader and the Chinese traveller Yidu. So, speculations are ripe that Aslaug and Ragnar might call off their relationship in the upcoming sequel.

For Bjorn, it is time to plot revenge against his beloved uncle Rollo for betraying his father. "He's so hurt and he's going to kill him. Bjorn is so straight-edge in that when he makes a decision, he sticks to it," Ludwig told Zap2it.

Explaining further about his character, the actor said, "In his eyes, there's certain things you can't forgive. The fact is he turned his back on [Bjorn] and our entire community for himself and there's no coming back from that."

So fans of "Vikings" can expect to watch the story of love and betrayal in season 4, which is scheduled to premiere on History Channel in 2016.