Many of the posters to this board claim the ghosts were merely hallucinations or metaphorical in nature. If that's so, then why did the dog whine before multiple appearances of the ghost haunting Michael? And why did both Michael AND Lena hear that ghostly moan at Lena's rental house?
"No *beep* sh*t lady, do I sound like I'm ordering a pizza?" - John McClane
I don't think the idea is that the ghosts within the story aren't real; more that the film uses them as representations of something emotional/psychological, if that makes sense.
In any event, the dog could be responding to *something* unusual--but something natural--but Michael's state of mind is interpreting it as ghostly. So that's the other way of reading it.
If I'm remembering correctly, I'm not sure the scary sceam at the cottage is even necessarily meant to be a ghost within the story...obviously they are both fearful, but it could have been some sort of animal. It's not settled that it *is* a ghost within the story, I don't think.
My opinion is they were just cheap jump scares that didn't belong in this film.
share