When retired hitman’s wife goes on vacation with her friend, she asks him to look after the friend's teenage daughter. Things go awry when he is forced to use a little violence to protect the girl from juvenile delinquents, but then they are found dead and the girl is kidnapped.
Ae-ran, a mother who is proud with her son hears a shocking news that her son, Dohoon, who left the military has developed schizophrenia. Afraid of losing her perfect daily life, Ae-ran decided to hide his son's illness. But her secret life that seemed to be smooth started to change when Kyeong-hwa, the only person who knows her secret appeared, gradually turning her anxiety into madness.
Seo-Jin Yoo is an actress, known for Gajokeui Bimil (2014), Secret Garden (2010) and Poomwiitneun Geunyeo (2017).