Cha Do Hyun is a rich heir to a family company with one major problem. Due to suppressed childhood trauma, he suffers from dissociative identity disorder manifested in 7 unique personalities who are out of his control. In order to overcome this disorder in secret, he hires a first year medical resident to help him heal by killing off each personality one by one.

Gong Shim rents out her rooftop room to a pro-bono lawyer in order to fund her art study abroad, consequently turning her life upside down.