It's a good story, but I wouldn't say it's a good movie. The boring kind of horror, although I use the label loosely because it feels more like a psychological thriller with ghosts. The first 15 minutes were pretty slow and uneventful, then it sort of picks up the pace (briefly) before falling back into slow exposition.
It felt to me like it was trying to do what Crimson Peak does, but poorly. The ghosts weren't the bad guys, psychologically twisted people were. But, where CP has a killer atmosphere and many moments of high tension/outright horror elements as the mystery unravels, the tension in Things Heard & Seen is very low aside from the ending, where it becomes predictable instead (especially since the beginning spoilers the ending two-thirds of the way in).
Not only that, the mystery relating to the ghosts is pretty easy to figure out and, while I liked the reveal that nothing George ever did was his own merit, it was also very predictable that he would go on a killing spree. I did enjoy the context clues they gave to let us figure out he was a manipulative narcisist from the get go, though, and watching him spiral. The "pushed to action by the evil ghost" thing feels weak, though, as did the whole cheating subplot.
