Yan Dan is the only descendant of an ancient tribe, the four-leaf scorpion. Since ancient times, her whole body has been a treasure of medicine. She and her twin sister Zhixi were able to cultivate into human form at the Queen Mother's Feast a hundred years in advance and encountered the biggest trial in her life - the love trial. She fell in love with Lord Ying Yuan but had to spend the next 800 years forgetting him. However, at this time, Yu Mo suddenly entered her life, and become her great support. Every day, Yu Mo takes Yan Dan out to do good deeds. One day while they were punishing evil, they meet Lord Ying Yuan's current reincarnation, Tang Zhou, who is currently a demon hunter. They help Tang Zhou search for the four ancient artifacts, and also discover a mysterious secret.

During WWII, Taiwan was occupied by Japan. Hai Sheng, a young man from Taiwan, was deeply influenced by Japanese militarism. He enthusiastically joined the Japanese vanguard and went to the mainland China to participate in the war together with his foster-brother, Yamamoto Ichiro. However, when he witnessed the atrocities of the Japanese army killing Chinese civilians, he only wanted to escape back to his hometown. On the way back home, Hai Sheng met four girls including Ning Yu. Forced by desperation, Hai Sheng agreed to send them to the occupied Nanjing city. Along the way, Hai Sheng not only had to protect the four girls, but also avoided the pursuit of Yamamoto Ichiro, the captain of the vanguard team. In the end, among the four girls, only Sakurako (Ying Zi), who was of Japanese descent, survived. When Ying Zi also saw the true face of the Japanese soldiers, Hai Sheng decided to work hard to cover Ying Zi to break out of the Japanese army camp.