Gu Qingxuan, a weapons expert, transmigrated into an orphaned lady of Northern Guard Manor in Daqing Dynasty. Imperial court sent her to barbarian territory as sacrifice for Royal Alliance Marriage. Trapped, she activated "Wumu Weapon Manual" system. She captured enemy leader, cut alliance marriage flag, gathered Northern Guard soldiers, and embarked on revenge, defending country, reviving military banner with her military industry expertise and strategic wisdom.