Su Mi and Su Yeon return home after an extended illness and hospital stay. Things have not been the same since their mother passed away. Their return is welcomed by Eun Joo, their stepmother. It's evident that Su Mi, the older and stronger of the two, isn't afraid to speak her mind when it comes to their family troubles. Su Yeon is timider and wary of their stepmother and looks to Su Mi for help. Continually picked on and harassed by their stepmother, the two have no choice but to endure the relationship for their father's sake. Su Mi promises Su Yeon that she will never let their stepmother beat them again. Unexplainable things start to occur at the house. Something has changed, no one knows what it is, but the sisters can feel it. On their first night back, Su Yeon hears someone running up the stairs, opening her door, and walking up to her bed. As soon as she pulls the covers over her head, they are pulled right off, yet no one is around. Could it be their stepmother trying to torment them? Or could it be that there's something more sinister at work, a supernatural force in the houses that wants to drive everyone away?