Very loosely based on the books. Being someone who is a diehard Mortal Instruments series fan, this was not even correct in any sense aside from the names. I understand creative licensing, but this went too far. It could have been so wonderful if they had just stuck to the books more instead of trying to change it because they felt it wasn't creative enough. I could go on for days about everything that is wrong with this book but I will try to sum it up. Casting was wrong, the story was wrong, it was just all wrong. This deserves no stars. The people that enjoy this clearly are just into the romance that doesn't represent what the book did. Pick up the book if you want to know the real story that was written.