From the start of the movie you know Cathy has problems (the movie description gives it away.) This knowledge doesn't ruin the movie at all. It actually works out better as we get straight to the good stuff so to speak, instead of some boring slow mental breakdown we have something more interesting. The tone is just right. Very natural and well acted. It quickly became a little bit boring due to lack of character and plot development. I kind of wished Cathryn had started sane now. The isolation from the lonely house didn't help give us anything interesting either. It was cliché. Even the disturbance around the character of Cathryn were cliché.
Slow burner movies like this need lots of atmosphere. Setting it in the hills in an isolated house was merely a veneer Not enough. Where was the atmosphere from the characters? The movie focuses heavily on one character, yet she's underdeveloped. Her journey is non existent.
There is nothing terrible about this movie either. It started off perfect and I was keen to watch it. Can't say any of the disturbing scenes disturbed me either. Overall it contained to many pitfalls that someone making a movie in this genre should have avoided.
Maybe one day I'll give it another go