simonsays89 — 3 years ago(March 09, 2023 06:31 PM)

I'll be honest and say that this isn't my own theory.
So we can assume that the reason these characters have the same name is simply because Carpenter was paying homage to Hitchcock, and also possibly as a nod to the fact that Jamie Lee Curtis is Janet Leigh's daughter. But this theory states that they are, in fact the same person.
In Psycho, we're introduced to Sam Loomis, lover/boyfriend of Marion Crane. Crane is of course murdered by Norman Bates, and it's Loomis who winds up tracking him down, apprehending him, and handing him over to the authorities. It seems it's all's well that ends well, except let's think about what Sam just went through; his girlfriend, possibly the love of his life, is murdered brutally by a deranged lunatic suffering chronic mental delusions. The movie doesn't show us how he is after all is said and done. the pain, the rage, the grief, the feeling of helplessness. So maybe Sam decides to transfer that rage to something positive, and ensures that what happened to himself, to Marion, Hell even to Norman, should never happen to anyone else. So he goes back to school, and begins studying psychology. After a year or two, he decides that the memories are too much where he is and takes an internship at the Smith's Grove Sanatorium in Haddonfield, where he decides to specialize in child psychology- after all, Norman's mental problems were rooted in childhood, so if he wants to stop another Norman from ever being created, best to weedle this out at the core.
It's shortly after transferring to Haddonfield that Sam is introduced to a small, seemingly unassuming child who murdered his own sister in cold blood- Michael Myers. Sam immediately decides this is his chance to make up for what happened with Norman, and throws himself into Michael's treatment, even using him as his case study for his doctorate. But the more and more he tries to reach Michael, the more and more frustrated and frankly alarmed he becomes that there is no apparent cause of Michael's psychosis. Whereas with Norman there was a clear root cause- his relationship with his mother- Michael seemingly just woke up one morning and decided to start killing people. This is something Sam takes as an attack on everything he believes, everything he tried to rationalize to give some meaning to his girlfriends death. And so, he realizes that all he can do is keep Michael locked away. And sure, the stress of all of this could easily explain how he gains a few pounds and loses his hair.
Really think about Loomis' actions in Halloween. Upon hearing that Michael has escaped, the first thing he does is arm himself and go to hunt him down like a dog. These are not sane and rational actions, especially for a man whose job it is to deal in sanity and rationality. These are the actions of a man who's dealt with a psycho killer on the loose before; a man with chronic PTSD. He hunts Michael relentlessly for five movies because he's so Hellbent for atoning for what he views as inaction that got his girlfriend killed. In Michael, he sees not just a dangerous murderer, but a walking embodiment of his failures. Of how his attempt to make sense of a tragedy only lead to further carnage and pain.
TLDR; After his girlfriend is killed by Norman Bates, Loomis becomes a child psychiatrist, and is tasked with treating Michael Myers. Doesn't really work out for him.