Overrated as hell, by no means this is a 77/100 movie (Current Metascore rating). Furthermore, this is mislabelled. It's not horror neither thriller. This is a sci fi drama. Many people who are gonna watch it in order to get scared or enjoy themselves, will be disappointed. This is not an enjoyable movie neither mindless fun. Plot is really heavy.
However, this has nothing to do with the movie. It's not director's fault it's mislabelled or overrated.
Actors are very good. Always a pleasure watching "Carla" from SCRUBS, she is definitely skilled enough for more dramatic roles. Marin Ireland nailed it, too.
Plot was really heavy though. I didn't expect something like this. To be honest, if i knew this was a sci fi psychological drama, i wouldn't watch it, at least these days. So, if you are in the mood for a sci fi drama with very good acting performances, a drama about motherhood above all, you will probably like it more than me. I didn't enjoy it, therefore I cannot recommend it. Remember, this has nothing to do with horror.
In any case, it's not boring and the ending is rushed.