Vikings Season 2: Will Rollo Really Fight Ragnar?

Vikings' first season saw Ragnar (Travis Fimmel) claw his way up from farmer to Earl, but the History Channel series was only getting started. "I'm amazed by Season 2. So much happens and it moves at such a pace. It's like blink and you'll miss it," Clive Standen, who plays Ragnar's brother Rollo, tells TVGuide.com.

When Vikings returns Thursday (10/9c), Ragnar will find everything he's worked for threatened by his brother's betrayal, new enemies in England and even his own ego. Standen and Katheryn Winnick, who plays Lagertha, break down exactly what viewers can expect from Vikings' anticipated second season.

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Ragnar's fling with Aslaug will have huge consequences: Ragnar's used to facing outside threats, but inVikings' second season, the Earl will find himself caught up in family drama. Thanks to loudmouth Bjorn, Ragnar's infidelity with Aslaug (Alyssa Sutherland) won't stay secret for long. "Their relationship will be tested ... and her relationship with herself changes," Winnick tells TVGuide.com.

Things will become especially complicated when Aslaug shows up unexpectedly at Ragnar and Lagertha's door — pregnant no less. Lagertha is then faced with the decision of sharing her home or abandoning everything she's fought so hard to protect. "You will be surprised by where she goes," Winnick says. "But what doesn't kill you does make you stronger really, one way or another."

Vikings will also jump ahead four years following the Season 2 premiere, resulting in the formerly pint-sized Bjorn going through a major growth spurt, with Hunger Games' Alexander Ludwig taking over the role of the now-older Lothbrok boy. "The dynamic changes, of course, because here's a young boy who's coming into his own and turning into a man and he now becomes a strong warrior in his own right," Winnick says. "So it'll be interesting just to see the dynamic between father and son and if it does change indefinitely between mother and son. That's her only child that she has left."

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A Vikings vs. Vikings battle will be unlike any fight we've seen: In its freshman season, Ragnar's men repeatedly displayed the ingenuity of Viking battle strategies. But how will these warriors fare when they're up against their own people?

"I think the difference is the Saxons had no idea how to fight the Vikings. The Vikings have their own tactics and they're very versed in skills of battle and war, but when you have Vikings against Vikings then they both know each other's tricks, so the tricks like the shield wall you saw in Season 1 aren't going to work against one another," Standen explains.

Add to that the fact that the premiere will find Ragnar facing his own brother in battle and it's clear the stakes have never been higher on the History series. "Ragnar and Rollo have gotten to the point where they can only really settle their differences one way and that's on the battlefield," Standen says. "So the tensions are high anyway because there's a lot of big emotions involved. ... It's going to be a bloodbath."

"I think Ragnar's genuinely afraid to face his brother," Standen adds, noting that while Ragnar might be the born leader, it's Rollo who's the born warrior. And don't expect Rollo to hold back just because he's facing down his former friends and family. Lives will be lost, but we won't spoil whose. Just keep your fingers crossed for your fan favorites, because no one's safe this season.

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Rollo's betrayal was a long time coming: "I think it's not a question of Rollo doesn't love his brother. It's about how much he hates himself," Standen explains of Rollo's decision to align with Jarl Borg (Thorbjørn Harr) in the Season 1 finale.

Rollo's frustration at being in his brother's shadow has always been evident, but his betrayal still came as a shock for most viewers. Especially because not long before, Rollo even endured excruciating torture to protect Ragnar. But everything has a price, Standen explains, and what Earl Haraldson (Gabriel Byrne) was offering at the time wasn't enough.

When Jarl Borg offered Rollo a shot at the power he always coveted, Rollo took it — and maybe Rollo's ambition isn't the only thing to blame for this betrayal. "I think Ragnar's gotten too carried away with his own ego and become obsessed with what he can be and where he can travel within Viking society and he's kind of forgotten his family just as much as Rollo has," Standen says.

But Rollo's decision to turn against Ragnar and fight with Jarl Borg will have consequences far beyond the battlefield. Citing a Viking saying, "bare is the back that has no brother," Standen hints that Ragnar and Rollo might need each other more than they think.

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Ragnar will face his toughest enemy yet: When Ragnar leads another raid to England, he won't find victory quite so easily this time around. Unlike King Aelle (Ivan Kaye), King Ecbert of Wessex (Linus Roache) has previous experience dealing with Vikings. "Ragnar kind of meets his match," Standen teases. Though Winnick says the Vikings will also have evolved since their first trip to Europe. "You will see their battles get more complicated and more strategic and that's exciting to see. You can see they're not only fighting with their physical attributes but also with their intellect," the actress reveals.

In addition to advanced weaponry and tactics, Ragnar will also have the support of King Horik (Donal Logue) when he goes up against the King of Wessex. "King Horik has many hidden agendas, but not all of them may be scheming," Standen says. Viewers can expect to explore Horik's motivations throughout Season 2 and Winnick warns that what we learn might surprise us.

Vikings returns Thursday at 10/9c on History. Are you excited for Season 2?