After finding out Chloé has been blackmailing people from running against her as the class representative, Marinette decides to nominate herself for the position. Wanting to prevent Marinette from winning, Chloé organizes an autograph session by rock musician, Jagged Stone, to bribe her classmates into voting for her. Meanwhile, Armand D'Argencourt, Collège Françoise-Dupont's fencing teacher, has just lost the Paris mayoral elections by a landslide. As the press continues to mock him, Armand is influenced by Hawk Moth and becomes "Darkblade", an armored black knight (according to his heritage), who zaps people, transforming them into an army of armored knights to overthrow Paris.