In the matching ground, the Commander of Unit 731 declared the whole unit has to emergency retreat back to Japan. To avoid the reveal of secret, all the evidences of the research of Germs must be totally destroyed before the withdrawal. In the laboratory, Ito is carelessly injured and infected with plague germs. In a hurry, Akiyama helps him to get in the only one train for retreat. The train is kept on running, a nurse Tama is also infected. Ito and her become the sources of epidemic. In such case, everyone in the train compartments are highly scares. The train is becoming a fatal deadly train.