The movie begins in a laboratory in Seoul, where Dr. Yang is conducting experiments to bring his deceased daughter back to life using lizards and alligators as test subjects. Several officers arrive to stop his dangerous experiments, but an earthquake devastates the nation. Three years later, the city has turned into a wasteland, with mutated alligators roaming freely. Sunna, living in poor conditions with her grandma, crosses paths with Giwan and Nam Son, who save her from thugs. The thugs reveal the existence of a facility with clean water for the chosen few, sparking curiosity and conflict.