An exact premiere date for the second half of "Vikings" season 4 has yet to be announced, but History has already shared a first look of what's bound to happen when the series returns.

Of particular note is the time jump that will occur. The show is expected to focus more on Ragnar's (Travis Fimmel) sons, who are now all grown-up. After his defeat in the first half of the season, Ragnar returns home to find that his sons have matured. Not only that, he'll also learn that his ex-wife now has a new love interest.

As seen in the recent trailer (below) from San Diego Comic Con, season 4 will also highlight Lagertha's (Katheryn Winnick) journey to seek revenge on Aslaug (Alyssa Sutherland), Ragnar's current wife, who had attempted to kill her in season 4A. But as expected, Lagertha is not one to back down so she sets off to fight the Queen of Kattegat.

Lagertha comes back strong and radiant. And with a female lover by her side, she is determined to defeat Aslaug. She was even heard saying in the teaser video: "I will never forgive you for taking away my husband, my world and my happiness." The Earl of Hedeby's new lover was revealed to be Astrid (Josefin Asplund) and she can be seen staying by Lagertha's side during her battles and excursions.

As explained by series creator Michael Hirst during a phone interview with Entertainment Weekly, Astrid has "become a part of Lagertha's life. They are in a relationship."

"You can well imagine why Lagertha might now be in a relationship with a woman, because all the men she's been involved with have betrayed her and let her down," Hirst continued. He also teased that the upcoming season 4B will be the "endgame" for Lagertha and Aslaug.

"Vikings" season 4B is expected to return to History sometime in fall.