설경구

Sung-geun

박해일

Tae-sik

윤제문

Chief Oh

Lee Byung-joon

Professor Heo

류혜영

Yeo-jeong

장소연

Nurse

이규형

Cheol-Ju

박민수

Young Tae-sik

손영순

Sung-geun's Mother

배성우

President Baek

Son Sang-kyung

Big Guy

전국환

President

이준혁

Gi-cheol

정인겸

Director

김세동

Older Alumnus

이현걸

Bus Jumper Man

윤세현

Demonstration Student

채수빈

Girl (uncredited)

정해균

King Lear (uncredited)

민경진

Principal (uncredited)

허준석

Neurosurgeon (uncredited)