Kyoo-man Lee	...	(Director)
Hyeon-jin Lee, Kyoo-man Lee	...	(Writer)
Yong-woo Park	...	Kang Ji-seung
Seung-yong Ryoo	...	Hwang Woo-hyeok
Dong-il Song	...	Detective Park
Ji-ru Sung	...	Jong's father
Yeo-jin Kim	...	Jong's mother
Byeong-eun Park	...	Kim Joo-hwan
Jin-mo Ju	...	Department head Ahn
Gu-taek Kim	...	Wol-il's father
Mi-hyeon Park	...	Won-il's mother
Sang-hee Lee	...	Yong-ok's father
Deok-jae Jo	...	Dong-pil's father
Young-hwa Seo	...	Dong-pil's mother
Sang-baek Nam	...	Cheol-woo's father
Ui-soo Lee	...	Cheol-woo's mother

Summary: The film is based on a true yet unsolved murder case from the early 1990s that is known among Koreans as the "disappearance of the frog children." In 1991, five elementary school students told their parents that they were going to hang out on a nearby mountain to catch frogs. They never came back.