Detectives in 40 minutes (Korean Horror Movie)

11:40 a.m., 4th period. Top student Jeong Hun (Yoo Seung Ho) walks into the classroom and finds his classmate and rival Tae Gyu (Jo Sang Keun) dead, murdered in cold blood. Ten minutes later, Da Jeong (Kang So Ra) walks in and sees Jeong Hun next to the corpse, covered in blood and seemingly the prime suspect. Everyone else is in gym class. 5th period is in 40 minutes. Believing Jeong Hun to be innocent, mystery buff Da Jeong teams up with him to find the real killer before the next period. The countdown begins NOW!

Korea's little brother Yoo Seung Ho stars in the real-time school suspense 4th Period Mystery. Growing up onscreen since The Way Home, the popular teen actor plays a high school student rushing to solve a murder mystery along with newcomer Kang So Ra. The film is directed by Lee Sang Yong, who assisted on My Dear Enemy and Swindler in My Mom's House, and co-stars character actors Park Chul Min and Jeong Seok Yong as teachers.