It's not bad, but I think it tries to do a lot of things at once, and as result does not get particular good at any of them. There are multiple plotlines (which is fine, of course), and they do make sense considering the circumstances, but most of them feel quite shallow. And investigation bits are not that compelling.
On one hand, that's all understandable, since it's based on real life, and real life is not that "dramatic" most of the time, but this is a TV show, so some extra dramatization could be beneficial. As is it feels more like they had specific points in a plan, that needed to be checked off, and they did just that.
On the other hand, the show has moments when it tries to be almost like a "thriller", especially with some choices in music, and with some camera shots. As if there is some mystery, but there actually is no mystery at all. If the same tension was applied to the whole series, especially to parts related to relationships inside the family - it probably would have had more impact.
This is still a decent watch, though. Annaleigh was great, other actors were not far behind most of the times as well. "The Cranberries" in the soundtrack? And it is way more cohesive compared to Good American Family, that started around the same time and is also based on true events.
