The movie begins with thundering bgm giving a erie feeling to the whole initial thought process of the viewer. The lighting and the camera perspective adds to the effect of the island that has the facility for the criminally insane people.
Frame after frame, the movie keeps the viewer guessing and the momemtum continues till the very end. For some people, the guessing might continue even after the end.
A great fitting climax, suspenseful storyline, excellent characterization - all make it a fantastic movie. Go watch!