there is no innocence to be lost

in this film everithing discover to be disturbing.
2 teenagers decide to kill a guy.but why really?just to satisfy one of alices caprices?is it enough as a motivation?alice likes said but probably is irritated by the way he aproaches her.so in her mind this conflict deforms in some kind of sick personal vengeance.and poor luke is her instrument to satisfy this obsession of her.what is luke really for alice?the cruelty of emotions in this film is outstanding.i believe the film needs a deep psycanalitic research to find which are the sources and the forces of a mind that can turn the sexual attraction into a cruel murder.any ideas?
one explanation could be that luke and alice dont know the difference between wrong and right.for luke this theory could be applausable(the forest man told him also in a certain part of the film)but for alice it doesnt fit.she seems to be perfectly coscient of her convictions.the scene in which she reads the poem in the class or when we hear her read her diary you can understand that shes a really mean person,or mentaly disturbed.anyway both of them have planed the murder of said and the robbery in the jewellery but how could be so naive to think that they can get away from this without getting caught?i dont know, I liked a lot this movie but i have too many questions.if someone find this topic interesting i would appreciate another point of view.