"Mom said: Not all superheroes wear capes." Mi-kyung gets a call from her son, Yi-su, who embodies her hopes and dreams. Yi-su tells her that the water bill at his accommodation where he is taking an exam has gone from a cheap price to a terrifying $1,000. She decides to go to her son's place to find out. When she gets there, she finds that the other people living there are suspicious and apathetic. As she searches for the reason behind the ridiculous water bill, she befriends Kai-tae, an employee at the management office. Mi-kyung soon realizes that she is in the middle of a huge problem.