ONE: 하이스쿨 히어로즈

Lee Jung Ha

Kim Eui-gyeom

Kim Do-wan

Kang Yoon-ki

Kim Sang Ho

Kim Seok-tae

Kim Joo Ryung

Myeong Da-bin

신준섭

Nam Seung-Sik

이찬형

Sung-Wook

Shin Jae-whi

Lee Ki-Yoon

Im Sung Kyun

Kim Seung-joon

Yuk Jun Seo

Lee Geol-jae

유희제

Choi Ki-soo

임현태

Choi Hong-il

Hong Min-gi

Kim Nam-hyeop

신현수

Kim Su Gyeom [Eui Gyeom's brother]

하민

Kim Ui-gyeom Aunt (Eps 3)