The college entrance exam is just 200 days away, and as the top twenty students in school begin a cram course that will help them get prepared for the big test, an ominous development finds them fighting for their lives. In a school system where students are evaluated solely by their grade, the pressure to succeed is so great that mental breakdowns have become fairly common. All the studying has taken it's toll on the weary students, and as they sit at their desks sleeping, the gentle refrains of "& Fue Elise" drift over the public address system. Suddenly, an image of top student Hye-yeong appears on the television screen.

She's trapped in a water tank, and will soon die if nothing is done. When a voice prompts the students to decide Hye-yeong's fate, the race is on to save her life. But who is Hye-yeong's abductor, and what do they have in store for the rest of the students?