Su Zhenghuai and his family boarded the train bound for the provincial capital. Just as it was about to depart, the train was attacked by a swarm of mice. Unfortunately, Su Zhenghuai's son was bitten and fell into a coma. In order to save his youngest son and many passengers who were bitten, Su ZhenghuaiSu Zhenghuai and his daughter Su Ting decided to take a risk and go to Xiaobaihe Hospital to get medicine, thus starting a rat run.