Not sure whats the whole hype on rotten tomatoes or even other forums, praising such a bland plot.
Well if leaving one simply confused is what's making trend these days without any solid storyline, then here's a story I've got for you that's even better:
Once I was taking a stroll on a completely secluded beach with no one around. After a while I could see a couple coming towards me from distance. As they walked past me, for no reason whatsoever the wife gave a stare and "sudden smacked" me right across my face and continued walking silently on their path while I stood there totally blindsided by what just happened! While it took few seconds for me to recover from shock, I slowly turned back to ask the reason for confrontation just to find nobody in the entire beach for miles and miles. Ever since that, never on a moonlit night I've walked all alone on a beach.
I hope last one minute read gave you way more chills than what this movie could not deliver in 2hr 18mins.