Director Osgood Perkins has become one of the most exciting new voices in horror in a short time, and largely thanks to the mystery he builds around his projects. Both tactics worked, with horror fans now looking forward to Perkins’ next film with bated breath. “Why does it always have to end?” asks Maslany’s character, “Liz,” in the new Keeper trailer. They’re questions anyone in a long-term romance will ask sooner or later — and maddening enough on their own. But there’s another layer to Keeper just under the surface, one that will cause plenty of screaming, bloodshed, and creepy lurking in dark corners.