4th Period Mystery (2009)

Korean Title: 4Gyoshi Churi Yeongyeok
Other Title: The Clue / Detectives In 40 Minutes / Fourth Period Murder Mystery
Year: 2009
Director: Lee Sang-yong
Genre: Thriller
Country: South Korea
Language: Korean
Subtitles: English
Cast: Yoo Seung-ho, Kang So-ra, Jo Sang-geun, Jeon Joon-hong, Jeong Seok-yong, Park Cheol-min
Runtime: 86 mins

During fourth period, high schooler Da-jeong finds his 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.

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