Occulus (2013)

When Tim is released from a mental institution where he's been  confined since age ten,  sister Kaylie meets him and immediately tells him they need to fulfill their promise of destroying a mirror.  Tim's not happy about this since he just got out of an asylum and doesn't need to do anything that's going to get him sent back.

When Kaylie and Tim were children, their family moved to a new home. An old mirror they purchased contained a spirit who possessed their father and made their mother crazy.  After their father murdered their mother, Tim killed him in self defense. But what police officer is going to believe the story of a screaming kid who says it was the mirror, not him, that killed his parents.

Kaylie convinces a reluctant Tim to go back to their childhood home to confront the spirit in the mirror and destroy it.  There are cameras set up around the house and Kaylie plans to tape everything so they have proof of the evil spirit.  Poor Tim, this  is not going to help his mental health.

Once everything is set up, and they start their investigation, the two find they can no longer tell what is real and what is a hallucination.  The viewer can't tell either.  There are flashbacks to the events of their childhood which complicate things further.  Is it a flashback or are the characters thinking about past events?

I'd heard good things about this and have seen it on multiple lists as one of the best horror movies of the year, but I'm not impressed.  There were some great scenes, such as Kaylie biting into the lightbulb.  Even I thought she was stupid, it still made me wince.