On a cold and murderous night, the scarred girl Sienna (Allison Lange) stumbled into the road. She was immediately taken to the hospital, and under the questioning of agent Zane (Jason London), the frightened Sienna finally told the horrible experience. Two weeks ago, she and her friends Scott (BJ Britt), Jason (Nick Holmes), Ben (CJ Thomason), Shannon and others who were studying at the medical university went out to play. They stayed in an ancient castle, and everything seemed full of excitement and fun, but this supreme joy was soon overshadowed. Behind them, there seemed to be a deadly doctor with a scalpel in his hand, and the footsteps of death were getting closer and closer. This group of ambitious future doctors has become the deadly victims on the operating table...