This is basically a 'group of teenagers are locked into a creepy house and then horrible stuff happens'-horror-movie in book form. Unfortunately one of the things it shares with these types of movies is that the plot can only happen because most of the people involved act very stupid. I could just about accept that they would take the party-invitation of a guy they don't know and who even refuses to tell his name because part of the group would feel tempted by that and go 'Hell why not? That sounds cool!' while the others would just get dragged along. However I could not really suspend my disbelief and accept that nobody recognised Gavin. Even if he hadn't any close contact with Lisa, only four years passed since Fearscape happened and it's hard to imagine that she'd forget the face of the guy who (almost) ruined her best friend's life but no...even when later in the book somebody points out that Val is terrified of him because he reminds her of someone she's all 'Well he looks a bit like Gavin but no that's totally impssible!'