This is an old school thriller that offers much more than the typical violent outbursts and spouts of anger. Actually, what makes this movie stand above those is that it can illicit the same emotions from the audience, all the while keeping every scene calm (albeit sinisterly calm) in nature.
Something that is wonderfully consistent with Christian Slater since the start of his film career and that still continues today is his ability to convey the psychology of his character to the audience.
Slater portrays Mark Collins, a young teenager who is in his own mind superior to those around him. He despises weakness and finds all of his strength from the wrong sources. Without his parents knowing, he has the ability to hear every word spoken in the house and thus has found out about his mother's indiscretions and his father's alcoholism. Even though Mark doesn't reveal verbally his thoughts of such behavior, Slater does an awesome job (as always) making it clear that Mark views his parental units as weak and unworthy of respect or devotion. In the same disgusted manner, he views the bully at school, his little sister, and the babysitters.
This is the only character that Slater has ever portrayed that may be innately evil. JD of Heathers and Robert Boyd of Very Bad Things had serious character flaws and far from the greatest means of handling problems, but I don't believe either were evil. Mark Collins is a different story.
He shows no affection whatsoever for anyone. Even small animals are viewed as only specimens. Art and music are only seen when surrounded by violence and commands. He has such a desire for order and control. This is the reason he can't foresee going to a strict academy which his parents wish to send him to. There he not only loses control because he will be under scrutiny but also because he will lose his footing as such a strong individual. At home, he is surrounded by people weaker and dumber thus making him confident in every action he commits.
He hasn't an issue forcing thorazine down the throat of his sister as long as he can vocally assure himself he won't be to blame. He was the starting of a mad scientist who was too smart for his own good.
This film has never been released on DVD and is out of print on video. If you can find it, BUY IT! It's an outstanding movie!