Heeseung is a criminal who was captured by the police for three murders.. He is the D-rated criminal of the jail.. As he is the most dangerous and short tempered guy in the jail.. Always fighting with others until the opposite is sent to the hospital.. No one dares to cross his path.. One day the jail needed a new doctor since the last one ran away after Heeseung's threat.. Dr Kim Sunoo.. a cute and beautiful looking guy came as the new doctor