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.

Kim Tae Hyun is a promising young surgeon, but his finances take a dive when his sister's health condition requires costly dialysis treatments. When Tae Hyun subsequently falls into a vicious cycle of debt, he assumes the alias of "Yong Pal" and begins making house calls for criminals who are willing to pay top dollar. Complicating things further, Tae Hyun gets involved with Han Yeo Jin, a comatose patient at the hospital.