In a security facility housing only captured serial killers, something or someone is picking off the inmates.

In the middle of nowhere, there lies a secure facility housing only serial killers. One morning the doors are open and the guards have vanished, but a strange freezing mist surrounds the building, preventing the inmates from leaving. Then, one by one, they are murdered. The survivors bicker, fight and blame each other, but the thing that's killing them looks suspiciously like a traditional 'victim'... A babysitter in a shower, a cheerleader, a camper...—Anonymous

Convicted murderers in a high security prison wake one morning to find that the guards have all gone, the doors are unlocked and the place looks 'sick'. But they can't leave because there's a mist, and it bites. It's not long before the inmates start getting bumped off, but is it one of them doing it or is it someone else? The inmates are just dieing to find out.—Richard Collins