A crack of thunder jerks you awake — or is it the unrelenting pounding of your heart, drumming on your rib cage in time with the raindrops on the roof? Either way, there’s a pool of cold sweat drying on your pillow, an oily unease dripping down your spine, and no rest in sight. You are alone, your door is closed, and the knife (thank God!) is still clutched in your white-knuckled hand.

The moonlight imprints the walls of your room with the dark bars of the window frame and hundreds of shadow raindrops. A flash of lightning, and then thunder again. You wring the bedsheets with your free hand and remind yourself to breathe. The nightstand nearby is still shrouded in darkness, so while you can discern the outlines of the picture frame you cannot see its contents. You reach out for it, trembling.

You freeze. There is a knock on the door.

You know who it is.