"Vikings" Season 4 is all set to return for its 16th episode titled "Crossings" that will mainly focus on Ragnar's first-born son, Bjorn. With that being said, History has finally released the official plot synopsis and the promo clip for the said episode.

According to Inquisitr, Bjorn Lothbrok's (Alexander Ludwig) fleet will continuously make an effort to keep sailing towards their destination which is supposedly the land bordering the Mediterranean. However, according to some reports, the said journey will not be smooth and that his team will have to face turmoil.

Bjorn's fleet will launch a surprise attack, as per "Vikings" Season 4 episode 16 synopsis. TV Guide notes, "Bjorn's fleet launches a surprise attack, while Lagertha's (Katheryn Winnick) quest for power continues in Kattegat."

In addition to that, the promo clip shows Floki (Gustaf Skarsgård) telling King Harald Finehair (Peter Franzén) and Halfdan the Black (Jasper Pääkkönen) that they will have to kill him before killing the people they meet. Consequently, Harald affirms that he wants to get rid of Bjorn, and therefore Ragnar Lothbrok's (Travis Fimmel) legacy. They'll maybe sort out their differences in the wake of their quest.

Furthermore, other "Vikings" reports claim that another lead character is going to die before the current installment ends. This is no other than Lagertha (Katheryn Winnick) who killed Queen Aslaug (Alyssa Sutherland), the mother of Ivar (Alex Hogh Andersen, to claim power in Kattegat and who's still on the quest for more power.

"Vikings" Season 4 episode 16 is titled as "Crossings". The upcoming episode is scheduled to premiere on Wednesday, January 4, 2017, at 9:00 p.m. ET on History Channel. The series is also scheduled to air in Australia on SBS One next Wednesday, January 11, 2017, at 8:30 p.m. Watch the upcoming episode's promo in the video below.

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