Seo-Jin (Kim Moo-Yul) is a popular architect. He suffers from a trauma when his younger sister Yoo-Jin went missing. His sister’s disappearance occured when Seo-Jin was a child. 25 years after her disappearance, Yoo-Jin comes back to her family. Seo-Jin feels something is not right with Yoo-Jin (Song Ji-Hyo).