Yu Oh-seong as Joon-seok

Jang Dong-gun as Dong-soo

Seo Tae-hwa as Sang-taek

Jung Woon-taek as Jeong-ho

Kim Bo-kyung as Jin-sook

Gi Ju-bong as Mustache

Joo Hyun as Joon-seok's Father

Jeon Young-woon as Dong-soo's Father

Lee Jae-yong as Scar-Eye

Kim Hyun-ji as Tall Woman

Yoo Seung-il as Child Joon-seok

Jeong Hee-ryong as Child Dong-soo

Kim Joon-beom as Child Sang-taek

Kim Seong-bok as Child Joong-ho

Kang Shin-il as Sang-taek's Father

Kwon Nam-hee as Sang-taek's Mother

Park Nam-hee as Joon-seok's Mother

Lee Eun-joo as Sin-ae

Kim Jung-tae as Doruko

Yoo Byeong-seok as Small Guy

Kim Gi-yong as Jjang-ga

Jung Ho-bin as Eun-gi

Yang Joong-kyung as English Teacher

Kim Kwang-kyu as Math Teacher

Kim Gi-ho as Cowardly Gangster

Hong Seok-yeon as Security Guard

Ahn Chang-gook as Man with Gold-framed Glasses

Jo Yong-won as Beauty

Kim Hoon as Doruko's Henchman

Jo Soo-jin as Member of Rainbow

Lee Se-na as Member of Rainbow

Kim Hyun-sook as Member of 7 Princess

Jang Gi-hoon as Small Guy's Mob

Kim Yeong-heon as Joon-seok's Driver

Seo Byeong-do as Vice President

Kim Jun-hee as Trans

Park Hyo-jin as Theater Advertisement

Park Yong-chan as Buckle Student

Im Ji-moon as Triangle Student

Kim Tae-won as Gangster from the Trunk

Kim Seong-hwa as Arresting Policeman

Bae Won-yeong as MC Student

Lee Dong-wook as Student from the Shaolin Temple

Kim Po as Mustache's Henchman

Ji Dae-han as Scar-Eye's Shadow

Cha Jin-ho as Bunting Student

Kim Ji-hoon-V as Weekly Duty Student

Kim Moon-bin as Student

Kim Jung-woon as Doruko's Younger Brother

Kim Yun-tae as Dong-soo's Henchman

Chang Yun as Dong-soo's Henchman

Moon Woon-bong as Dong-soo's Henchman

Son Byung-hee as Dong-soo's Henchman

Yang Ji-woong as Waiter

Lee Kyeong-ha as Bar Girl

Hwang Joo-hyeon as Bar Customer

Choi So-i as Female Employee

Yoo Sang-seob as Jaws

Lee Ji-yeon as Female Employee at Wedding Hall

Sun Ho-jin as Young Man with Umbrella

Kim Jae-hyeon as High School Boy

Oh Seung-chan as Court Prosecutor

Jeong Jong-seop as Court Lawyer

Park Chan-young as Judge

Kim Sung-nyeo as Bus Conductor

Jo Joon-baek as Employee at Construction Site