During the period of Republic of China， Su Zheng Huai， a junior officer in the Department of Health， went to the provincial capital to visit his relatives with his elder daughter Su Ting and his youngest son Su Yue Sheng. In the train， he met his younger daughter Su Ling. She had been missing for a long time. During the trip， the train was attacked by rats， and Su Yue Sheng was bitten and went into a coma. To save him and many other passengers bitten by rats， Su Zheng Huai and Su Ting decided to take the risk and go to Xiaobaihe Hospital for the antidote. It would be a dangerous， terrifying run.