“Windeye” by Brian Evenson.
I can still vividly remember hearing Evenson read this story (also the title story of his excellent recent collection, via Coffee House) at the 510 in Baltimore and gasping at a certain moment, when the terms change radically (you will know the moment when it arrives). A spooky, weird, haunting story about the confounding, multifarious nature of reality (among other things). I still think about this story A LOT, which is probably why I teach it (and often the opening paragraphs specifically, for a craft talk I do on story openings) so much. Here’s the first paragraph:
“They lived, when he was growing up, in a simple house, an old bungalow with a converted attic and sides covered in cedar shake. In the back, where an oak thrust its branches over the roof, the shake was light brown, almost honey. In the front, where the sun struck it full, it had weathered to a pale gray, like a dirty bone. There, the shingles were brittle, thinned by sun and rain, and if you were careful you could slip your fingers up behind some of them. Or at least his sister could. He was older and his fingers were thicker, so he could not.”