During the eriod of Reublic of China， Su Zheng Huai， a junior officer in the Deartment of Health， went to the rovincial caital 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 tri， the train was attacked by rats， and Su Yue Sheng was bitten and went into a coma. To save him and many other assengers bitten by rats， Su Zheng Huai and Su Ting decided to take the risk and go to Xiaobaihe Hosital for the antidote. It would be a dangerous， terrifying run.