The drama tells the story of Xie Xiang (Bai Lu) who disguises herself as a male student to join the military academy under her brother's name.
Hoping to follow in her deceased brother's footsteps, Xie Xiang enrolls into the Arsenal Military Academy in Shunyuan disguised as a male, with only her good friend Tan Xiaojun (Jin Xin) knowing her secret. There, she becomes good friends with the country bumpkin Huang Song (Liu Sibo) and the quiet Shen Junsan (Li Chengbin), all while getting into periodic quarrels with her hot-headed and playful roommate, Gu Yanzheng (Xu Kai). Despite her small stature and weak constitution, she gradually trains into an able soldier, winning the respect of her peers.
These students soon uncover a dangerous conspiracy surrounding the Japanese occupiers, the Chinese resistance, as well as past royal descendants of the now defunct Qing dynasty.
