On a changed continent, where nations fight to maintain peace, Lords host decade-long battles requiring Insignia'ers—warriors who bear symbolic insignia. April, a 16-year-old with premature aging, lives isolated in the Elite District. Her world changes when Kolbein, a young Lord from the North, offers hope: an antidote for her condition lies within a distant iceberg. He needs her as an Insignia'er for upcoming battles. April joins Kolbein on a treacherous journey north. They endure icy terrain and defeat a deadly ice bear to retrieve the cure. Kolbein is injured, and as April seeks help from the Southwesterners, they face the hostile Highlanders, led by Lord Lu-Han. A fight results in the death of Kolbein’s ally, Lord Aoto. Healed, April returns to the Elite District, then travels North with Princess Agneta to officially become an Insignia'er. As she trains, April grows stronger and embraces her heritage. Meanwhile, Kolbein, seeking revenge, challenges Lu-Han in a battle that will determine their fates and her future role as a defender.