Qian Su was originally the daughter of a poor family. Under the guidance of her neighbor Yuan Qing, a former first-class swordsman in the kingdom, she became a first-class female swordsman in martial arts. She wholeheartedly wants to become an official member of the royal guard in order to cure her mother's illness and bring back her father who is on an expedition. Under Yuan Qing's teachings for many years, she found that she slowly fell in love with Yuan Qing. In these difficult days, Yuan Qing died of illness. Full of grief and indignation, Qian Su won the first place in the Kingdom Swordsman Competition and successfully became a royal guard. At the same time, he was spotted and loved by the Crown Prince. The prince launched a fierce offensive. Once Qian Su married into the royal family, he no longer had to worry about survival. But her heart gradually became lost. She cannot fall in love with her husband. The prince went to Xisai in anger and left her a poisonous oath. Qian Su practiced hard and finally became the best swordsman in the country. However, as his martial arts became more and more refined, he could not find himself. Where will she go from here?