“The Good Neighbor” (2016) generally didn’t work for me.

My first problem was its premise.  Two teenage aspiring filmmakers play an elaborate high-tech prank on an elderly neighbor by installing hidden cameras in his home and then manipulating his environment: causing his lights and TV to malfunction, causing his windows to break, and even adjusting his thermostat to plunge the temperature so he’s forced to cope with the bitter cold.  They plan to mimic a haunting, and they rationalize it because he actually is a horrible person, well portrayed by James Caan in an understated performance.

Here’s what doesn’t make sense — what the teens are doing is against the law, and they know it.  (One explicitly states it at least once mid-way through the film.)  I count trespassing, criminal mischief and unlawful surveillance to start with, and I’m willing to bet they’d face charges for harassment too.  Yet they fully intend to makes themselves “famous” via the Internet with this cruel prank/documentary.  They shoot lengthy footage of themselves narrating the construction and implementation of their project; this is intended as part of the documentary.

But why would they upload detailed, inclusive evidence of their crimes to the Internet?  If they truly become “famous” with thousands of “hits” for their video, wouldn’t that mean countless people could bring them to the attention of the police?  (And, truthfully, even if they tried to remain anonymous, I’m sure any competent investigator viewing their video would at least count them as suspects.  One lives right across the street from Caan’s character.)

For much of its running length, “The Good Neighbor” actually succeeds at being a serviceable horror-thriller — if you can get past that hole in the premise.

But then we come to the second problem with this movie.  Towards its end, it takes an unexpected dramatic turn.  It stops being a thriller, and simply becomes a particularly sad drama.  I don’t want to say to much for fear of spoilers, suffice to say it’s a real downer.  But it isn’t frightening at all — or even terribly entertaining.

The only part near the end that pleased me was the movie’s final shot.  It was ambiguous, but it suggested a nice new level of character depth.  I thought it was neat.

Oh well.  Maybe others will enjoy this film more than I did.  I myself can’t recommend it, and I’d give it a 5 out of 10.

Postscript: you can have some fun here trying to figure out where you’ve seen these teenage actors before.  They’re both veterans of horror.  The mild-mannered one is Keir Gilchrist, who horror fans will recognize from “It Follows” (2014).  The meaner, more manipulative of the pair is Logan Miller, who played the goodhearted Benjamin in this past season of “The Walking Dead.”  It’s so weird seeing him play such different characters.