Plot hole: The group talks about Phillip's death. The doctor says Phillip's death was a sleepwalking accident, nothing more. Then the other doctor says it was suicide. How do you explain either situation when the door was padlocked with no way out to the very top of the building where Phillip fell?
Plot hole: The TV-watching girl is killed when Freddy shoves her face first into a TV set. (one of the more creative movie deaths.) But the thing is, all the other deaths have been set up to look like suicides if not accidents - this one was obviously foul play, since there's no way she could have launched herself into the glass of a TV screen hard enough to break it. We see that her body is found this way, but they make no inquiry.