A popular high school student, who is the top student of her class, mysteriously dies. Six of her friends who graduated from the same elementary school attempt to track down the reasons for her death. While the six friends try to find the truth behind her death, they struggle with teenage hardships and academic pressures.
Hong Jong-hyun
Park Ji-yeon
Lee Joon
Han Ji Woo
Shin So-yul
Kim Bo-ra
Choi Myung-kyung
Lee Mi-so
Yoon Hee-seok
Kim Dong-beom
Jung Woo-yeon
Go Kyung-pyo
Jung Kyung-ho
Choi Woo-hyeok
Nam Hyun-joo
Jeong Man-sik
Jeon So-min
Lee Il-hwa
Jo Jae-yun
Song Eun-jin