In an alternate 16th century, the Tudor dynasty's legitimacy doesn't come from God, but from their bond with the last great dragons of England. When Mary I ("Bloody Mary") ascends the throne, her dragon is not a noble beast of fire, but a sinister, vampiric Wyrm that feeds on Protestant "heresy," casting a literal shadow of terror. Her half-sister Elizabeth, hidden in the countryside, discovers her own latent bond-not with a dragon, but with a fierce, intelligent water-drake from the Welsh lakes. To claim her crown and save her country, Elizabeth must rally a rebel alliance of hedge-mages, break Mary's bond with the Wyrm, and lead a draconic civil war for England's soul.