Date: August 12, 2009

Rating: PG-13

Genre: Crime, Mystery, Thriller, Action

Length: 1h 26min

User Score: 58.64%

Description: During fourth period, high schooler Da-jeong finds her classmate Tae-gyu dead in a classroom and Jeong-hun standing in front of him with blood on his clothes. In order to stop Jeong-hun from becoming the prime suspect, Da-jeong must help him find the real murderer, who is still inside the school building, under 40 minutes before period four ends.