I find that you can easily divide the movie into two halves, the first is the childhood of Mike Myers, and the second is after several years when he has grown into a behemoth of great size and strength.
The first half of the film really set it apart from the typical serial killer-slasher horror film because it gives you an origin story for Mike Myers. When his psychologist comments in his lecture later in the film that Mike is a perfect combination of nature and nurture creating a psychopath, it only confirms what you see in this part of the movie. It is quite clear that Mike is a troubled child; normal kids do not kill and mutilate animals (which is one symptom of the childhood psychological disorder of conduct disorder/oppositional defiant disorder. This disorder is a prerequisite for the adult disorder antisocial personality disorder, more commonly known as psychopathy or sociopathy), even under stress. You see what his family is like and how he is bullied in school. I find that you could really sympathize with him to the point that when he goes off to kill the bully and his family in his house you could understand why he’d do such a thing. Even though those were quite heinous murders, as a viewer, you could still feel that to some extent he was justified in doing so and that he was reacting how poorly he is treated. He is not portrayed as just a “pure” bad guy (like Freddy in the latest A Nightmare on Elm Street movie, for instance, who was an abusive pedophile even while still alive), rather Mike Myers’ backstory adds a certain dimension to his character.
The second half of the film fit in more with the standard serial killer plot, Mike Myers goes to a certain town and kills people one by one. Except he isn’t there for the express purpose of killing people, but to look for his baby sister, Laurie. (Now, I could understand why he returned to his hometown to find her, but how on earth did he recognize her after fifteen years? She was adopted unofficially, her name was changed, and she doesn’t look a thing like her baby version. I view this as a small hole, but oh well.) This motivation seems quite different from the typical serial killer, who seems to be driven by purely evil intentions, such as revenge or the pleasure of killing. For the most part, Mike kills those who upset him or get in his way, or to achieve his goals.
The violence of Mike’s murders was undeniably excessive and served to emphasize how cold and uncaring he was. There are two points with regard to his murders that are of note – his use of masks and murdering teenagers as they engaged or after they engaged in sex.
It can be noticed that everytime Mike kills someone, he wears a mask. When he talks to his mother and little sister, he purposely takes off his mask, but when he has to interact with his father or sister, he seems to prefer to have to keep his mask on. When he is a child, it seems his mask creates an alternate persona for him. It adds a distance between him and his victim. His real face, as a child is described by his psychologist as “angelic”, but this seems to be his “real” mask. When he puts on his artificial masks, the clown, the plastic mask, or any of his papier mache masks, it seems to show who he really is inside, cold, emotionless, and detached. Eventually, he stops removing his masks and stops connecting (even talking to) with people. The only time he removes his mask in the second half of the film is when he tries to tell Laurie that he is her long-lost brother. I find it hard to say definitively whether he wears his masks for the purpose of detaching himself from his actions or to create a greater feeling of fear in his victims. Personally, I think that as a psychopath, Mike wouldn’t care a bit about what other people thought about him and wears the masks for his own sake, to be who he truly is inside. Whatever the reason behind the mask, it gives Mike power over his victims because he is able to stay unaffected by events behind his mask, while his victims are scared and unable to look back at him with the same clarity as he.
It also seems to be a theme in the movie for Mike to kill teenagers who are having sex. It seems too coincidental for Mike to come upon them while they are or after they have sex, besides there is no such thing as coincidence in movies. It seems to be a moral allegory against pre-marital teenage sex, where Mike punishes these teens very brutally because they had sex. But more than just punishing both teens equally, the females in the pairs seem to undergo a more tortuous experience. Mike spends more time with the females, scaring and humiliating them more. It’s as if the women committed a worse crime by having sex, which I find is simply sexist, but is the prevalent view of society today – it’s understandable for guys to have lots of sex because they are in possession of a stronger sex drive than women, but women are supposed to be pure and virginal, else they are sluts and whores who deserve no sympathy.