A mother lives quietly with her son. One day, a girl is brutally killed, and the boy is charged with the murder. Now, it's his mother's mission to prove him innocent.
Following the dumping of gallons of toxic waste in the river, a giant mutated squid-like creature appears and begins attacking the populace. Gang-du's daughter Hyun-seo is snatched up by the creature; with his family to assist him, he sets off to find her.
