Check out the creepy-as-hell teaser trailer for Grim Night, which looks like Dementors Gone Wild! Here's the premise: On a random night a collection of hooded creatures descend upon the Earth and just murder a crap load of citizens. It's written by two newcomers we're not familiar with but getting produced by by Bryan Bertino from The Strangers, which was horrifying. Check out the trailer for the movie that started out as a spec script that launched a studio bidding war (with Universal winning.)