While Rollo (Clive Standen) gets nice and cozy with his new wife and title in Paris, a new force has arrived on “Vikings” and could spell disaster for Ragnar (Travis Fimmel) and the Lothbrok family.

At the conclusion of the March 10 episode, “Yol,” King Harald Finehair (Peter Franzen) arrived in Kattegat and made it clear that he plans to become king of Norway — which means he’ll have to first topple Ragnar. That is an issue “Vikings” creator Michael Hirst says is going to play a major role in Season 4 — and he’s not coming alone.

“He’s a great character,” Hirst tells Zap2it. “He and his brother Halfdan the Black (Jasper Paakkonen) are incredible characters.”

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With both characters steeped in actual Viking history, Hirst says, “They are a threat to Ragnar and to Bjorn.” After all, Bjorn (Alexander Ludwig) has spent Season 4 thus far proving his worth as a man, to free himself from his father’s shadow.

Don’t expect an all-out war between Viking kings just yet though.

“The thing is whatever their long-term ambitions are, there’s always a short-term objective,” Hirst says. “In the short-term, it’s usually better for them to work together. They can put on hold their ambitions.”

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It’s going to be an interesting time for Ragnar, as Hirst explains, “You’re in that strange halfway house of you know this person probably wants to overthrow you, but in the short-term you need him. There’s a lot of fun to be had down the line.”

While he may prove to be an ally at first though, it’s important for Ragnar to keep his eye on the man who would be king of Norway.

“Harald Finehair is an exceptionally wonderful, brutal character,” Hirst teases.

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."