송중기

Wolf-Boy / Chul-soo

박보영

Young Sun-yi / Eun-ju

유연석

Ji-tae

이영란

Sun-yi

장영남

Sun-yi's Mother

김향기

Sun-ja

유승목

Professor Kang Tae-shik

Shin Bi

Dong-mi

우정국

Mr. Jung

구본임

Mrs. Jung

이준혁

Policeman

Soel Oh-shin

Thug 1 (uncredited)

Han Min-hik

Thug 2 (uncredited)

Chuay Kwong-lak

Thug 3 (uncredited)

Sung Du-hyung

Man in Black Suit 1 (uncredited)

Cha Jong-ho

Man in Black Suit 2 (uncredited)

서동수

Army Colonel (uncredited)

Jung In-gum

(uncredited)

Lee In-ho

(uncredited)

O Yeong-seok

Policeman 2 (uncredited)