在这部收敛动作/悬疑/惊悚片中,當警探班正在調查診所爆炸案發生原因時，突然發生另一次爆炸，醒過來後他發現自己躺在另一家醫院的病床上。這間醫院氣氛詭異，除了當班的護士、舉止古怪的警衛，和一個口中不斷喃唸聖經的醫護人員之外，幾乎看不到其他病人。還搞不清楚狀況的班，不久後又受到自稱復仇天使和其他若有所求的鬼魂干擾…
After suffering an explosion at the hands of a terrorist bomber, detective Ben Walls awakens in a hospital and is forced to remain inside the building at the behest of his Captain. As Ben navigates the hospital's alarmingly empty hallways, he soon finds himself hunted by a self-proclaimed avenging angel and haunted by apparitions whose deadly motives remain a mystery. Now Ben must find a way to both stop the supernatural forces that want him dead and catch the bomber before he strikes again.
