The first half of the 13th century is dominated by two women, as proud and ambitious as they are beautiful, yet different in all other ways. Isabella is a medieval Helen of Troy, flamboyant and passionate - wife to King John and mother to Henry III. Blanche of Castile, serene and virtuous, is Queen of France, wife of Louis VIII and mother of Louis IX. The two women hated each other on sight. Isabella will stop at nothing, not even murder, in her passion to destroy the French queen . . .