It's a director's job to get the best performances possible out of their actors. So maybe it's not shocking that egomaniacal auteurs with their name on the line will go to some pretty insane lengths to get the most out of their performers. But when the film you're directing is a horror movie, and the look that you're trying to capture is sheer terror, it can be a dangerous combination of conditions that often crosses over into flat-out illegality and tragedy.
Directors have filmed in terrifying locations; they've broken their actors down psychologically; and they've put their cast and crew in genuine risk - all for the sake of selling a few more tickets. For some actors, however, the director isn't the (only) problem. Veteran actors who've survived some of the creepiest horror sets possible can attest to that fact. Whether it's nearly drowning on a set with a very demanding James Cameron barking orders at you or making it through the night in a haunted hotel, casts and crews on horror movies have lived through some pretty terrifying on-set situations.