When her son who lives in a single room is given an outrageous $1,000 water bill, a mother decides to become a detective and find out what is behind it.
박지영
as Lee Mi-kyung
조복래
as Gae-tae
Kim Dae-hyun
as Lee Ik-soo (#404)
허정도
as Kang Ha-joon (#403)
Baek Soo-jang
as Oh Deok-goo (#301)
이솜
as Kyung Jin-sook (#402)
이성욱
as Lee Tae-gil
Oh Chang-kyung
as Park Se-joo
강진아
as Constable Song
Kwak Jin-mu
as #303
Jeon Go-woon
as Examination Graduate Student
Kwon O-kwang
as Examination Graduate Student
