Because OMG THIS IS PERFECTION (x50,000,000) isn't the best, most coherent review, I'll try to add some more thoughts.  SGJ love for horror and the slasher genre in particular is so very evident here.  He knows just how to weave such a compelling story in a genre and sub-genre that feels often overlooked.  This is easily one of the most engrossing horror novels I've ever read, and if I hadn't already read and loved a lot of SGJ's other works, this would be the one to confirm what I already know.  He's one of my favorite authors ever (not just in horror, but any genre).  Just an absolute master in the craft!