In order for the government to construct a dam, an entire town is evacuated and then submerged under water. The artificial lake that forms is called Lake Seryeong, and Hyeon-su is a security guard employed to stand night watch over the dam. On his first night driving in, Hyeon-su accidentally hits and kills the young daughter of a locally respected property owner, Yeong-je. Panicked, Hyeon-su decides to dump the body in Lake Seryeong. While searching for his daughter, Yeong-je discovers that Hyeon-su is responsible for her death. Instead of seeking justice, Yeong-je wants an eye for an eye, and his plan for lengthy, vicious revenge unfolds. Meanwhile, Hyeon-su is consumed by guilt for killing Yeong-je’s daughter, but when confronted with Yeong-je’s revenge, Hyeon-su ignores his rightfully deserved penance and instead, reacts with his own anger.