Morally ambiguous, the Spiritual Heaven Sect is an influential sect that has remained in seclusion for years. Its Young Lady, Ling Xuan, encountered a pair of dying siblings during her travels ten years ago. In exchange for saving the younger sister's life, she proposed a ten-year pact with the young man. She brought him into the Shadow Pavilion of the Spiritual Heaven Sect for training. If he could survive and graduate ten years later, he would become her assistant. The young man fought desperately and finally left the Shadow Pavilion alive with a new name, Ying Shi. However, the Spiritual Heaven Sect has fallen into a vulnerable state. Ling Xuan's father, the sect leader, coveted the Wanxin Technique and wanted to take it away from her mother. He incited chaos in the martial arts world and even turned against his own daughter. Forced to protect herself and devise a counterattack, Ling Xuan must disguise herself as a useless fool who is unreasonable and ruthless. At this very moment, Ying Shi is sent by the Shadow Pavilion to approach Ling Xuan in search of the Wanxin Technique. Through suspicions, testing, and dangers during their journey, they eventually build complete trust in each other. However, just as they have fallen for each other, Ling Xuan discovers the secret of Ying Shi's birth.