Even at only 70 mins, it runs out of story; great beginning

Not sure what went wrong with this; it started off really well but the last 30 mins, it just collapsed into people running, screaming, bloody murders, throat slittings.
I don't really know what it all meant--two kids saw ghosts when they were kids, as did another women who took pills to make them vanish--but that interesting idea is dropped and some crazy cult takes over? A bit of a mess, but nicely done in the beginning. If they had kept that tone, it would have been a compelling film but it's short--only 70 mins--and I guess than ran out of story.