Question....and pls don't slam me.....some things went over my head.

It's fun that people debate things, but you should never expect to be able to find the ONE, TRUE interpretation in a movie like this.

I don't think Gordon had been a patient at hat hospital years earlier because he wouldn't have RECENT pictures of his newborn baby there. More likely, he simply put them up there while he was staying at the abandoned hospital that week (or Phil could have done it for some reason when he had his wallet). But why does he put them up among Mary's pictures? Why does he try to call his wife while sitting on Mary's headstone? Most importantly, why does Mary's alternate personality "Simon" talk to him? All that suggests to two are both possessed by the same evil spirit.

However, Mike never ever actually hears "Simon" talk at the end because he's NOT THERE when that part of the tape plays (and the whole movie has become entangled with Gordon's hallucinations by that time) which suggest that he may not necessarily be Mary's alternate personality and that all these things COULD be just be eerie coincidences and Gordon has basically just gone crazy. But then THAT begs the question of how does Gordon even KNOW about Mary? (His being at the hospital with her twenty years earlier seems far-fetched to me).

So which of these is it? I'd actually say it's unresolvable and is meant to be unresolvable. So it's not a bad thing that you can't figure everything out.

The film deliberately leaves the nature of "Simon" up to our interpretation (which is part of what makes it so cool).

1.) Simon could be just one of Mary Hobbs's personalities which manifested when she killed her family. Gordon later has a psychotic break and develops his own “inner killer.” This is supported by numerous instances where Gordon is shown to be highly stressed and about to crack from the pressure of a new baby and a struggling business. Most creepy things that actually happen in the asylum (like random sounds and the weird things Hank sees), can be explained by Gordon walking around the hospital in his sleep (as shown in flashback), as well as former patients who are sneaking in and squatting (which is mentioned when they explore the hospital for the first time). In fact, there was apparently a subplot in the screenplay that actually revealed a homeless woman to be living in the hospital and further squelched the need for a supernatural explanation. This is the most realistic interpretation but it doesn't quite explain why Gordon hears Simon's voice. Perhaps (and this is reaching), he could have heard it on TV in connection to the hospital during the media scrutiny and lawsuits of the 1980s. Or perhaps when Gordon has his breakdown, he develops his own "alternate" voice in his head which just happens to sound a lot like Mary's "Simon."

2.) Simon could be a metaphor for the insanity people bury deep inside themselves and which can come out when they are "weak and wounded." In this case, the moments where Gordon seems to hear Simon's voice are not literal but rather artistic flourishes of the filmmaker, similar to how we see strange imagery of the bugs around the Asylum as Mike describes the Satanic Ritual Abuse Scandals.

3.) Simon could be some kind of psychic phenomenon generated by the hospital. A lot of insanity happened in that place and one interpretation of the film is that this insanity is somehow contagious. In some ways, it's not all that different than the basic idea of The Shinning (enough evil things happen in a place that it develops an evil energy). Evidence for this theory is found in how most of the crew is affected by the hospital. Yes it's Gordon who kills everybody but Mike develops a pretty extreme obsession with the Mary Hobbs case and even Phil seems to get rather paranoid the longer they stay there, first fearing Hank, then Wendy (Gordon's wife), and finally Gordon himself.

4.) Finally, the most supernatural interpretation is that Simon is actually some kind of evil spirit who possesses Mary, lays dormant for a number of years, and then poses Gordon when he enters the hospital for the first time. The evidence for this theory is:
a.) Gordon appears to hear Simon's voice a number of times even though it seems VERY unlikely that he would be familiar with her. Furthermore, the tapes of the Sessions were kept in a sealed "evidence" box which Mike broke into. Even if Gordon did know about Mary Hobbs, there wouldn't be any way for him to know what her "Simon" persona or what her "Simon" voice sounded like.

b.) When looking at the timeline, Gordon seems to go nuts INCREDIBLY quickly. When viewing the property for the first time, he's worried about his business but still fairly rational. He even tells Phil that he doesn't want to rush the job and would rather be "safe." However, shortly after entering the hospital (where Simon can influence him), he immediately switches gears and becomes reckless (saying he can do the job in one week). He then goes home and murders his wife and child over something that was obviously an accident. He never hear any mention of Gordon being a violent man or one to easily lose his temper (in fact, Hank says that Gordon is the only person who never loses his cool); so his extreme changes in behavior seem to indicate another presence. Mary seems to have gone through an equally quick transformation. One moment she’s a sweet little girl, the next she’s murdering her whole family, including her parents (who hadn’t even hurt her).

c.) Simon says, “I live in the wounded and the weak.” He tells the doctor that people let him in so can do these awful things. Both Gordon and Mary are LITERALLY wounded right before they commit their first crime. Mary falls on her glass doll (cutting her chest), and Gordon is badly burned by the hot water. Various mythologies have references to evil spirits who can enter through wounds which is exactly what Simon appears to be doing.

d.) The fact the filmmakers chose to CUT OUT the subplot involving a homeless woman living in the building indicates that they wanted the audience to leave room for a supernatural interpretation.

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