Rollo's loyalty lies with Paris and he is determined to prove it in the next episode of "Vikings" season 4, titled "What Might Have Been," by personally taking down his brother.

In the episode, Ragnar and his men charge into his brother's new home, ready to burn it to the ground. Getting there won't be easy as the inclement weather will threaten their odds of making it there alive.

Of course, it is not for them to be slowed down by harsh weather conditions. In the upcoming "Vikings" season 4 episode, Ragnar is determined to push through with the mission, even if the weather forbids them.

As the Norsemen get on with their journey, Rollo will be waiting for them prepared and outfitted for a war. From the looks of it, Ragnar's brother is now all for bringing Paris out of Ragnar's crosshairs for good.

In the promo for the next "Vikings" season 4 episode, Emperor Charles can be seen pleading for Rollo's help as he convinces him to turn his back on his brother. His need to make this appeal seems to hint that Rollo has this lingering desire to reconcile with his brother.

"Please save Paris. Don't return to your brother," he urges Rollo, who was certainly moved and encouraged by the emperor because he is already on the battleground ready to fight.

Locked and loaded, Rollo and his men wait for their enemies to arrive. Ragnar failed to see this coming judging by his stunned reaction in the "Vikings" season 4 trailer.

Rollo is not one to give up now. He is determined to prove to Princess Gesla that he will help Paris and that his allegiance will always be with them.

When the princess first met Rollo, she was not all too keen on marrying him. Things started to change when she saw how determined he is to win her over by fully committing himself to helping Paris.

The next episode of "Vikings" season 4 will see a whole new bloody warfare brew. "Vikings" season 4 episode 6 "What Might Have Been" airs March 24 at 9 p.m. ET on History Channel.