Sloppy waste of potential

Rating: 5/10 (2 October 2015)

I usually love Whedon's material, and this meta-horror movie definitely had some good ideas and great potential, but ultimately it disappoints. The sloppiness of the writing simply makes it hard to enjoy.
The good stuff is the scattered snippets of Whedon's snappy dialog, and the concept.
Spoilers follow.
The bad stuff is exemplified by the puff of smoke that makes one character suddenly change his mind, and say the exact thing that they wanted him to say. I mean, I can tolerate the sci-fi approach where they somehow built a huge Truman-like enclosure and somehow invented the technology for an invisible barrier. But brain control that makes people think and say exact illogical things with a puff of smoke, is way too much.
And this is the kind of thing I hate with bad sci-fi and fantasy writing: If you are going to invent a superpower or super-technology, don't make believe that it doesn't exist when it isn't convenient. Why didn't they use that puff of smoke to stop them from driving away into the tunnel instead of rushing to blow it up? Or use it to stop them from going into the elevator? Or from killing zombies? And why not make them run into the monster's hands for that matter? Evidently they don't care about freewill after they chose the monster, since they used the puff of smoke. Not to mention that they made most of the characters so dumb that they would ignore things like cellar doors opening by themselves and tunnels blowing up.
And what kind of stupid monster facility has a big red button available to guests that brings ALL of the monsters into the facility and frees them? That's really dumb. And why didn't the monsters attack each other? There are several more examples like these of lazy writing that insult the audience.
Other flaws include many bland or nonsensical characters in the facility (no one seemed to be bothered by the fact that they are killing people even if it's for the greater good), and there's the weird redneck character that never made any sense (biblical preaching over the phone but afraid of being heard over speaker-phone? why?), all of which makes it impossible to tune into what they were about.
And then there are the various rules on how to kill their sacrifices. Obviously, all of the rules are just there so that they will conform to horror movie clichés. But it isn't clever to simply invent a 'system' that conforms to horror clichés if they don't give any reasons why these rules are there!
In short, the concept in the movie feels very undeveloped and the writing is too sloppy. Good idea, a moderately entertaining movie, but a poor execution.