Months later, a letter arrived without return address. Inside, folded small as a prayer, was a photo of a sky at dusk. Written on the back in careful block letters: Thank you. Below that, a set of coordinates Aiko did not recognize at first. When she mapped them, the coordinates pointed to a tiny cemetery beyond the outskirts of the city, a place she had driven past without noticing. The next day she drove there, ipzz005 secured to the bed of a pickup, a single sheet of rag paper laid flat in the passenger seat.