A nurse is seen cowering in a corner with her panties pulled down.

Several scenes early on that take place in the cafeteria that show some inmates suddenly going into a rage and throwing something, slamming on the unbreakable glass between he cafeteria and the kitchen, trying to attack each other, in each instance a guard puts them in a choke-hold to subdue them and drags them out of the cafeteria.

A man tasers another man's eyesocket and eye (results are not shown).

We see a thick trail of blood and gore after the decapitated man's body is pulled (offscreen) down a hall and into another room.

A group of inmates take turns slamming heavy objects at the thick bulletproof glass that separates them from the kitchen. The window doesn't break, but because they are repeatedly using things like chairs, tables, and metal ladders to hammer at the glass, it comes out of the frame and the inmates rush the kitchen that way.

We see the body of a decapitated man slumped against a wall, his severed head rests in his lap.

A man gets a delivery of meat including chickens with their heads left on. Later the man accidentally drops part of the delivery on a tile floor, the meat inside bursts apart and meat, blood, and innards splatter everywhere. While cleaning it up, he sees some kind of bloody animal skull that's definitely not a chicken, it's much larger.

A man is shown facedown on the floor, minus his head, there's a quick shot of the bloody stump and he has a very large pool of blood surrounding him.

A man hurls a heavy telephone at another man's face, breaking his nose.

A man is knocked unconscious when he's hit in the back of his head with a metal fire extinguisher.

A man grabs and twists another man's broken nose, the man with the broken nose screams at the top of his lungs in pain.

A lot of cursing Fuck, Shit and other profanities said frequently.

The violence is intense and almost non-stop with only brief respite. The entire movie is intense, and characters spend the last half of the movie badly frightened, some in total panic.

The inmates are frightening and threatening. After the blackout, the suspense level is very, very high.