Considerably Better Than Expected (SPOILERS)
So I just watched this on Hulu, and though there are parts that leave something to be desired, by then end of the film I found myself laughing more than most comedies of today. The ending is certainly played for laughs and with that in mind perhaps some of the bad dialogue found earlier comes with the same intention.
There are awkward points in the setup, but once the ball gets rolling you see a sort of home invasion with a social networking element that does bring about modern horrors. I was genuinely surprised by the conclusion and especially surprised that Monkey lived. Introducing a dog in an R film today means its almost certainly getting killed off to get a cheap reaction out of the audience.
I don't see the girls' motivation as an issue. I knew several girls in high school who very well may have done this.
If those viewing Knock Knock were expecting Fatal Attraction, they may have been disappointed to get such a strong black comedy vibe and down voted. 7/10
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