Cast out after being framed for harming the brother who grew up beside her, Isadora learns she belongs to the powerful Silverwood bloodline. Secretly the famed physician known as X, she breaks the brutal curse tormenting Sebastian, while a pendant leads her three brothers to their missing sister. As jealous Ophelia steals her formulas and joins Celestia in a deadly plot, Isadora faces repeated attempts on her life. Shielded by Sebastian and her newfound family, she reveals the traitors, severs the Sollow connection, and accepts Sebastian's heartfelt proposal.