In early 20th-century China, as war rages against the Imperial Japanese army, young men are drafted to defend the northeast. Determined to serve, Xie Xiang disguises herself as her brother and joins the military. Proving her skill, she earns a place at an elite academy in Shanghai, where she befriends fellow recruits, including the headstrong Gu Yan Zheng and the quiet Shen Jun San. As they train and grow stronger, the cadets take action against enemy forces. But tensions rise when both men develop feelings for Xie Xiang, complicating their mission. Amid war and sacrifice, she must balance loyalty, identity, and love while fighting for justice.