Lights Out wasn't a bad film, and it's always nice when a horror film comes out that has some scary moments and is only PG-13. Usually I go into PG-13 horror films with low expectations, which allowed me to enjoy the movie for what it is: a bunch of jump scares. The short film this movie was based off was simple, and effectively scary. By adding so much to the concept, it threw off the pacing. This film tried to be more than what is was. It tried to explore a deeper meaning, touching on mental illness and family problems (think The Babadook but not nearly as good), but it only managed to scratch the surface in a pretty shallow and uninteresting way. This was only accentuated by sub-par acting from quite a bit of the cast.
However, the film succeeded in making Diana frightening. By not ever showing her real form for much time outside of the shadows, she managed to be pretty horrifying. Definitely a creature to inspire nightmares when you turn out the lights.
Overall it was fun to go see in a theater filled with jumpy teenagers, but not really worth a second watch.