Why is Sister Mary Eunice still called Mary Eunice even in flashbacks where she's a teenager? When nuns are named "Sister Mary <something-something>" it's usually as the name they took when they took holy orders.
Or if they had traditional Catholic parents.
Or a time saver. Rather than explain that nuns take on new names when they join, just as an explanation for that one bit, it could have just been easier to call her "Mary Eunice" there as well.
Did the Enfant Terrible get away with her crimes? Wouldn't the police find it just a bit suspicious that her entire family was killed in the same manner as her friend was earlier? That she is claiming the same man who killed said friend also killed her family? They must have some file about the case somewhere. Surely someone is going to notice the similarities?
The killings were only a few months apart IIRC, so it seems like the same file should still be open and probably would be worked by the same cops. They might very well find it suspicious, but the girl is outside the narrative at this point.
...What exactly did those aliens want, anyway? They seemed to go to a lot of trouble for two of their test subjects to die, one of them to get pancreatic cancer and their kids to become a lawyer and a neurosurgeon.
In the end the point seemed to be creating those schizophrenia curing kids. Based on past stories with aliens creating human-looking kids, it is probably the prelude to an alien invasion.
Why did that prisoner look like the Angel of Death?
Sister Jude had lost her mind and imagined that the thug inmate was the Angel of Death come for her.
Why did the Devil/Demon act pretty feminine when it possessed Sister Mary Eunice? Does it take on gender traits?
During The Devil's brief lapses in control, we find out Mary Eunice is at least aware she's possessed, which means she could be aware of what The Devil is doing with her body. The Devil was likely acting sensual to further upset the neurotically chaste, "gynephobe" Sister Mary.
When Lana escaped from Briarcliff with the tape and got into the taxi why didn't Dr. Thredson alert the taxi driver that she's an escaped patient and take her back in there at the taxi driver's relief and approval? Even if she did start screaming and yelling that he's Bloody Face it would have sounded like insane rambling. Or would someone inspect the tape either way? though he could have taken it.
This bothered me as well. Revealing herself to him while he could easily have waved the taxi driver to a stop was idiotic on her part, and on his for just standing there as if he was not mere feet away from her.
Presumably Mother Superior explained the situation to the driver. All she had to say was "The woman I'm bringing you doesn't belong in Briarcliff, no matter what anyone else tells you. You drive away once she's in your car."
Lee killed 15 different people from 8 different families in one night. How is that even possible?
Because he's Santa Claus, of course!
Perhaps he only killed a certain amount of people in each house and left some alive (which has to be it, because if he killed entire, typical 3-5 person families, the number should be much higher than 15). And then, he may have tied up the ones he left alive so he'd have time to move to another house and kill more.
What exactly is the nature of the possession of Mary Eunice? Like at times it seems like the demon possessing her has complete control over her but at other times it seems more like it's influencing her actions more and that she's still got some form of free will even if it's just to do evil things. Some evidence to support the latter would be her recounting stories of being embarrassed in her youth to Jenny or the whole bit with "You Don't Own Me" and the crucifix.
Remember, the Devil has the ability to see into others' memories and desires; Satan simply looked into Mary Eunice's memories and recited them as if they belonged to him, which makes sense since he was posing as her at the time. As for the personal tone Satan took while saying all that, perhaps the Devil simply likes play-acting?