Continuity mistake: One of the prisoners is washing his face in a sink and there is a shot from under the water, where we see the man's face in a round sink. The next shot is from the cell and here we see that the sink is rectangle-shaped with only rounded corners.
Continuity mistake: When the prisoners escape, they lock the door of the cell and break the key, forcing the guards to go another way. But when Dr Thorn returns, the door is opened.