Insurance saleswoman Yoon Young (Lee Se Eun) is in charge of the hospital's last remaining patient Lee So Hee, who is in a coma. While the hospital's director hopes to avoid taking any responsibility for the patient, chief doctor Jang Seo Won (Lee Jung Heon) wants to keep the patient there at all costs. Ten years ago, the patient's young sister disappeared mysteriously. She was in a comatose state as well, and strangely reminds Yoon Young of So Hee.

Kang Su Jin (Myung Ji Yeon) is a veteran nurse in the hospital. She continues to be haunted by an accident that happened ten years ago in the operating room. She wants a fresh new start with chief doctor Jang Seo Won, but all he seems to care about is the hospital's only patient, So Hee. Su Jin tries to find this patient, and learn why she's stealing so much of her boyfriend's time.

Detective Choi (Im Won Hee) has lost his passion for life, and now pursues money and nothing else. He was in charge of a case 10 years earlier dealing with a girl's disappearance from the hospital. The only clue he holds is the girl's necklace. He's come to the hospital for only one reason: blackmailing the hospital's director. He needs money to raise his daughter and has to stop this hospital from closing at all costs.

Designer Hong Ah (Lee Young Jin) has a peculiar talent: she can see dead people. By now she's gotten used to the blood and horrible corpses, but one day a corpse appears, asking Hong Ah to kill her. She finds out about a patient in the hospital, a certain So Hee who is now in a state of coma.

The hospital's shut down is just a few days away, but chief doctor Jang Seo Won believes he can save his last patient, So Hee. Five people meet each other at the scene of his last operation and a mysterious series of murders starts.