Mishima is a typical spineless pushover who works as a repairman for the Exopolis Tower, Tokyo's largest and most popular high-rise business and entertainment complex. He promised to return home in time to celebrate his son's birthday, but when his pushy boss saddles him with overtime, the job keeps him occupied all night. On the morning subway train heading home, a massive earthquake strikes, collapsing both the Exopolis Tower and its underground train lines. Now Mishima is trapped deep underground with the other passengers on the train, some of whom are less than cooperative. Will he be able to take the initiative for once and lead them all to freedom, or will they starve in their underground prison?