Ragnar arrives in Hedeby where he is greeted by Astrid who remarks that her wet nurse told her many stories about him. While there, he apologize to Lagertha after she refuses to accompany him to England. Ragnar departs, though Lagertha and Astrid later arrive in Kattegat. Lagertha wishes to see Björn, who has decided to send messengers to Rollo in England.
With Ragnar, three of his sons and many others away sailing to England, Lagertha plots her revenge. Astrid lures Tagnar's remaining sons Sigurd and Ubbe into a trap and threatens to kill them both after Ubbe fails to attack Lagertha's guards. In the end, Lagertha is succesful in reclaiming Kattegat, killing Aslaug in the process and securing herself and queen.
Elsewhere, Ragnar meets his end and the news slowly makes its way back to Lagertha. Astrid consoles her lover after the death of her former husband. When Björn returns home, he and Astrid becomes lovers, perhaps to spite Lagertha (Astrid was upset that she does not fully reveal her plans while Björn is tired of being told what to do).
Lster Egil attacks Kattegat on Harald's orders; Lagertha, Astrid and Torvi. among many others, repel the attack. Astrid strikes Egil down, though Lagertha prevents her from killing him - she tortures him later for information.
Astrid is a strong shield maiden, who's inspired by Lagertha. She's intelligent and gives the impression of being loyal to her Queen, all the while having sex with her son. Astrid has shown to be slightly envious of Torvi as she as Lagertha's caunsel and respect
|Season four appearances|
|A Good Treason||Kill the Queen||Mercy||Yol||Promised|
|What Might Have Been||The Profit and the Loss||Portage||Death All 'Round||The Last Ship|
|The Outsider||The Vision||Two Journeys||In the Uncertain Hour Before the Morning||All His Angels|
|Crossings||The Great Army||Revenge||On the Eve||The Reckoning|