In 2020, an unknown virus leaked from a laboratory in the United States and spread rapidly around the world. After an incubation period, infected people undergo severe neurological mutations, lose their reason, and become intensely aggressive. Just one week after the outbreak, Deep City has already become a ruin. “This isn't a zombie novel. It's a story about how ordinary people become the kind of person they themselves despise in the apocalypse. The virus came from America, but the living are more terrifying than the dead.” “Survival doesn't need a reason. Just calculation.”