My opinion.
I thought it was okay. I gave it a 6.
There's a few big, big mistakes that really ruined for me though.
The direction was good, the effects were cool, the cinematography was excellent and the acting was marvelous. The script sucked.
SPOILERS BEWARE!!!
1) Kurt Ravn's character says "anyways". Most teachers I know guard the danish language like a Transformer guards the Allspark, okay? No way a danish teacher would use "anyways" in a sentence. A minor fault.
2) The articles from Ekstra Bladet (the web print the psychiatric shows Cecilie) is from the 70's. Since the web in its current form only has existed since the mid 90's and EB only has been online since the late 90's and you only can search on articles from the past two years, how is this possible?
3) When the doctors are talking about her case, even though there have been 3 or 4 other murders they mention Camilla straight away. No mention of the others and recent murders. I know she told the psychiatric her name but only from the newspaper clippings we are told that there are 3-4 other girls. The cops in Denmark are pretty great. Not many cases go unsolved. Murder cases anyways. Your bike is totally another discussion. How come they haven't caught him yet? You should think they at least looked at people working at the school. How did they not see his face on Arnold Schwarzenegger's body?
4) More of a question: She exits the main building to go to the janitors house. How come when she tries to escape she is in the same basement as in the main building? How come she had to go out in the stormy scary weather?
5) Lars Mikkelsen saying: "Stop dancing." when she is under hypnosis. I laughed out loud. Real loud.
6) The end scene where we see the ghost of the girl? And the scene with the mother. Ohh please.
I was so positive at first but please. Oh please. Entertaining though. Flawed but entertaining.