Dark River, the most mysterious assassin organization in the martial arts world, is composed of three families: Su, Xie, and Mu. The highest ruler of the three families is known as the TOP Leader. The top leader is currently suffering from a strange poison and is at the brink of death. Upon learning the news, the three families of Dark River seized the opportunity to launch a rebellion. Su Muyu, also known as Kui, the head of the Spider Shadow, the guardian squad of the top leader, sought out the divine doctor Bai Hehuai from the Medicine King Valley to cure him while also fending off the assassins from the other families to protect him. However, Su Changhe, his close friend in Dark River, has joined the assassination plot against the top leader on behalf of the Su family.