Lu Zheng, a sword cultivator from the lower realm whose sword bone has been sealed, makes a living in the Abandoned Sword Valley on the outer grounds of the Tianshu Immortal Sect. He rescues a young white tiger named Rustball and discovers that it can refine the essence of gold and iron. Starting out together as an outer disciple and a cat, they undergo the Sword Tomb trials and the sect competition, obtain the Heaven-Piercing Sword Case, and travel to the Myriad Swords Divine Sect in Zhongzhou. Alongside Mu Qingyao, Yan Mei, and Jian Xinglan, Lu Zheng ventures into the Myriad Manifestations Secret Realm, subdues ancient swords, and ultimately joins forces to repel the Poison Dragon Sect and defend their sect.