[s4e1] A - Good Treason

With Ragnar ill, Queen Aslaug consults the Seer about her own future on the throne, showing a clear shift in her loyalty.

Bjorn takes command, though his decision to arrest Floki is met with mixed emotions from a recovering Ragnar. [S4E1] A Good Treason

The episode opens with the Vikings returning home after their massive raid on Paris. However, the victory is overshadowed by a dying King Ragnar. He is haunted by visions of Valhalla closing its doors to him, leaving him in a feverish state of spiritual and physical crisis. With Ragnar ill, Queen Aslaug consults the Seer

While Ragnar struggles at home, Rollo remains in Paris to secure his new position. In a move that justifies the episode's title, Rollo fully embraces his "treason" by slaughtering the Viking camp left behind, choosing his new life as a Frankish noble over his own kin. However, the victory is overshadowed by a dying King Ragnar

In Hedeby, Lagertha deals with her own usurpers, reclaiming her power through calculated violence. Vikings - S4E1 - A Good Treason | Project Fandom

The biggest shock of the premiere comes from Bjorn Ironside. In a bold move to establish his own authority while his father is incapacitated, Bjorn publicly arrests Floki for the murder of Athelstan. This sets a dark tone for the season, as Floki is left bound in the town center to face judgment.