The Seer in his physical form was killed by Ivar the Boneless (Alex Høgh Andersen) in the original series.
Yet he continued to star throughout the remaining seasons as a vision, dwindling between the worlds of the Vikings and higher beings.
Many believe he is a god himself and chose to live in this physical form and fans are keen to find out whether he will return.
According to actor Kavanagh’s agency CV, the Dublin-based star is due to continue his role as the Seer.
His agency page says: “John recently completed filming on Ridley Scott’s feature film The Last Duel. He is currently filming the role of the Ancient Seer on Netflix series Valhalla.
“Other recent screen credits include the roles of the Ancient Seer and Pope Leo X in the History Channel’s Vikings.