Bong-soo loses his memories from an accident, which disables him to recognize his family. Due to this condition, and his ever-increasing odd behaviors, his relationships get mixed up. He treats his wife as his daughter and mistakes her daughter for a friend. Ironically, his friends and family start to accept the situation as they derive some comfort and warmth from it.

Seon-hwa is a new student at an elite medical school, and she is initiated into a dissection class headed by Dr. Han along with five other students, including her boyfriend Ki-beom. After the first class the students all start to share the same nightmare involving a one-eyed surgeon, and one by one they start to be murdered, the victims being discovered with their hearts removed. Seon-hwa and Ki-beom are convinced that these events are related to a beautiful cadaver with a rose tattoo on her breast, and they begin an investigation to uncover her identity.