The special effects are nice and the acting is passable, but this film is way too cliché and formulaic to be enjoyable.
The plot is the same as every single other "chick horror" movie ever. A pretty girl pisses off a ghost, has lots of scary visions, people don't believe her, she freaks out and acts crazy, at the end she discovers "a terrible secret". Bonus points if there's an old house and a mysterious magical person who knows all about the demon/ghost/spirit.
It's disappointing that a team of clearly creative and talented British people chose to use this tired clichéd formula instead of writing something fresh and new.
Too many horror films do this, it's predictable and boring and it needs to die. I refuse to believe that teenage girls are the only worthwhile demographic for horror.