The daughter of the distinguished Yuan family iskidnapped, loses her memory after waking up and her temperament changes drastically. She runs away from home in order to escape the engagement, changing her name into A Yuan and disguising herself as a small man catcher in Qinhe County. At the same time, Jing Ci is assassinated on the way to send his sweetheart to marry others. After he survives, he also comes to Qinhe County as a county official and becomes A Yuan's colleague, secretly protecting A Yuan. A Yuan devotes herself to punishing the treacherous, trying to keep the people safe. However, murders occur frequently in this mall county. Jing Ci and A Yuan are approaching the truth step by step, but also encounter heavy resistance. Soon, A Yuan discovers that she is not the real daughter of Yuan family, and Jing Ci is not just a small county official. When A Yuan breaks with Jing Ci and marries another person, another murder case occurs in the capital and A Yuan is suspected and jailed. In order to save A Yuan, sickly Jing Ci finally finds the instigator behind the scenes, and takes A Yuan away from the crisis.