The Setting: Why not take it all the way up to Alaska? There's something terrifying about a place where it's sometimes dark for 24 straight hours. Plus it's cold and isolated.
The Premise: You could go in a lot of directions. A snowed-in cabin, a haunted ski lodge, or even a creepy ice cave. The season could have a lot to say about human isolation, or disintegration of the mind in the face of confinement. Who can you trust when you're no longer sure who's inherently good?