A detective goes undercover as a high school student to investigate a case.
Kim Hye-yoon
Yoon Kyung-ho
Kang Hanna
Ryujin
Park Sung-woong
Kim Sung-kyun
Jang Young-nam
Jeong Man-sik
Kim Byeong-ok
Lee Seo-hwan
Geum Dong-hyun
