It's been a while since Ragnar left Lagertha for Aslaug on History's Vikings, but Lagertha hasn't forgotten the life she feels was stolen from her. In this exclusive clip from the next episode, "The Vision" -- airing Wednesday, December 7th -- Lagertha (Katheryn Winnick) confronts Aslaug (Alyssa Sutherland), who's in a bit of an "altered state," during a sacrifice ceremony meant to celebrate Bjorn's expedition to the Mediterranean.