'Vikings' Season 4 spoilers: New teaser released, hints of continuing battle between Rollo and Ragnar [VIDEO]

“Vikings” Season 4 premieres on Thursday, Feb. 18 on History and fans are treated with a new teaser video that features the growing sibling rivalry between Rollo (Clive Standen) and Ragnar (Travis Fimmel).

In the preview below, which was posted on the show’s official YouTube channel, one man will admonish Rollo for betraying his own kind. The man will get struck with an arrow, but he will issue a warning, “Your brother is coming. Ragnar will avenge us.”

Spoiler alert! This article contains “Vikings” Season 4 spoilers.

Betrayal was the theme revealed for Season 4, as seen in History Channel’s first promotional image, which is inspired by Leonardo da Vinci’s 15th-century painting of “The Last Supper.” “Vikings” creator and writer Michael Hirst told Entertainment Weekly that all the figures in the painting are concentrated around the words: “One of you will betray me.”

“I think that’s the key to understanding this image that we have from the show. It’s exactly the same issue that’s being confronted,” Hirst said. There are two people who are going to betray Ragnar again, he teased.

Based on the trailer, fans are anticipating if Aslaug (Alyssa Sutherland) will be the one committing treason against Ragnar. “I want to know if a woman will succeed to the kingdom of Kattegat,” she tells the Seer (John Kavanagh). “You mean after the death of Ragnar?” the Seer replies.

The preview video will also focus on King Ecbert (Linus Roache) in Season 4, who is reported to join forces with Ragnar in Season 4. The video will show that the king of Wessex will do anything to rule, even if it involves rubbing elbows with the devil. “I would sup with the devil if he would show me how to achieve my earthly goals,” King Ecbert says.

“Vikings” fans will also be given a glimpse at Ragner’s growing, blond-haired boys in the trailer for Season 4, as they ride off Paris.

The new Season of the Irish-Canadian historical drama will kick off with a premiere episode titled “A Good Treason,” according to Enstarz. The fourth installment of “Vikings” also has revealed the titles of its three succeeding episodes: “Kill the Queen (episode 2), “Mercy (episode 3) and “Yol” (episode 4). The show will be 20 episodes long, which will be broken up into two 10 episodes each.

“Vikings” Season 4 “Good Treason” will air on Feb. 18, 2016 at 10/9c on History.