In the attic of a rented farmhouse off Stillwater Road, Luna finds a locked footlocker tucked behind a water heater. The previous tenant, a quiet woman named Margot, left it behind. Inside: a high school yearbook, a prom photo, and a stack of letters tied with blue ribbon. The letters are from a boy named Caleb — who, according to Margot's sister, died the night before prom, seventeen years ago. Luna reads the letters in order, watching Margot's handwriting shift from giddy to frantic. The last letter isn't a letter. It's a single sheet of paper, folded into a tight square, with a sloppily drawn map of the attic floor. There's an X. Below the X, in Margot's shaking hand: 'He's still here. I can hear him breathing in the walls. You will too, soon.' Luna folds the map, stands up, and notices that the dormer window, which was closed when she came up, is now open a crack. She doesn't remember opening it. The air coming in smells like decay and cheap cologne.