써니

유호정

Na-mi

심은경

Young Na-mi

진희경

Choon-hwa

강소라

Young Choon-hwa

고수희

Jang-mi

김민영

Young Jang-mi

홍진희

Jin-hee

박진주

Young Jin-hee

이연경

Geum-ok

남보라

Young Geum-ok

김선경

Bok-hee

김보미

Young Bok-hee

민효린

Young Su-ji

김시후

Young Joon-ho / Joon-ho's Son

박영서

Young Jong-ki

천우희

Sang-mi

김혜옥

Na-mi's Mother

정석용

Jong-ki

하승리

Ye-bin

김영옥

Na-mi's Grandmother

Baek Jong-hak

Nami's Husband

정원중

Na-mi's Father

김원해

Teacher

김새벽

Class Monitor

Kang Rae-yeon

Jong-ki's Girlfriend

김예원

Girls' Generation Leader

류혜린

Girls' Generation Member

이경영

Joon-ho

Hwang Choon-ha

Past Detective

Bae Soo-kyung

Gang High School Girl

박순천

Woman in Past Picture

소희정

Homeroom Teacher

차태현

Insurance Company Main Model

이준혁

President of Private Detective Office

Han Seung-hyeon

Jung-mi's Older Brother

양희경

Jang-mi's Mother

주진모

Sung-chan

Park Hee-jeong

Young-jin

고준

Private Detective

Kwon Eun-soo

School Broadcasting Club DJ

Choi Yi-sun

Joon-ho's Friend

성지루

Choon-hwa's Lawyer

Eom Hye-su

Sang-mi's Group

Ahn Soo-ho

Judge

Yoon Jung

Su-ji

Jun Yoon-ji

Student Presenter at Festival

Choi Soo-im

Bully Female Student

Yang Joo-ho

Insurance Company Branch Manager

이상아

Woman in Past Picture

Lee Seung-heon

Joon-ho's Friend