This tells the story of Dao, Gao Fei, Han Xiao and others in a city's circle line subway who were met with a bizarre accident. After falling into the depths of the ground, they were attacked by a huge monster. While trying to escape, everyone was very flustered at first, and it was not until their teammates were getting killed killed one by one that they came to their senses, united as one, fought the monsters together, and finally managed to escape. The whole story is exciting and tense, with a tight pace and some humour and comedy elements, which make the whole story more attractive. At the same time, it mainly shows the different reactions of people with different identities and personalities when faced with a sudden disaster, as well as the different reactions between people in a disaster....