侦探Michael Turner对发生在高度戒备的监狱发生的神秘死亡事件进行调查，调查正在进行之中时，监狱里面接二连三的自杀及谋杀事件不断出现，是什么促使围墙内的这些囚犯做出这种极端的事情，Michael决定把事情查个水落石出。Detective Michael Turner investigates mysterious deaths that occur in and around a maximum-security prison. What begins as just another suicide and murder case unfolds into a furious struggle to uncover the unexplainable while escaping death at the hands of a vengeful spirit unleashed within the prison walls.