I saw this movie a few days ago and gamely jumped during the scary parts. I must admit, I found it pretty decent...until I started to THINK about what the characters were saying. Logical problems:
1. Her boyfriend, who seems to be a pretty fit dude, makes no sound while being killed. Don't you think that he might have at least tried to take the killer?
2. When the remark is made that the gym teacher is "SOOOO in love with Lisa," I almost screamed at the screen. When your best friend's family HAS BEEN KILLED BY A TEACHER WHO WAS IN LOVE WITH HER, you don't make comments like that if you have half of a heart.
3. As soon as Nash asks the uncle how many exits they have in the house and the uncle catches on that there may be danger ahead, wouldn't the smart thing to do be to get Donna, boyfriend, aunt, and uncle into a car and drive far, far away, then bait the house with the HRT and police force so that the killer has no way to get out?
I could go on. And on. And on. Basically, the plot was decent, the characters weren't profiled enough for you to actually feel any empathy when they were slaughtered and there were way too many errors.
HOWEVER.
This movie might be good for teenagers, or young couples just looking for a fun night out. If you don't consider all the goofs, it's a mediocre film.