Bo finally learns the identity of her mother – and that those closest to her have been keeping secrets. No longer sure who to trust, Bo decides to track down “Mommy Dearest” alone, in order to extract the truth about her own origins once and for all. While everyone frantically searches for Bo, Dyson visits an ancient Norn, a wish-granting, tree-dwelling crone, where – in order to protect the woman he loves – he makes a sacrifice that may change his relationship with Bo forever, as she prepares for a final face off with her deadly mother.