This is a thriller/horror genre movie, the kind that was very popular in the early 1990s.
Think “The hand that rocked the Cradle” or “Single white female”- if thats the kind of movie that you want, you will enjoy this. It feels quite up to date and it is an excellent addition to the psychological thriller canon.
My main criticism of the film would be how unpleasant all the characters are. Had it been released in the 1990s it probably would have received 5 stars but we expect even villians to have some redeeming features now.
Having said that, if you are in the mood for a creepy thriller, this film will satisfy that need very well.