At 11:40 that night, a shriek tore through the house, a siren so loud the windows shook. I stumbled down to the basement, where I had never seen anything but old boxes. Behind the shelves stood a gray steel door I had never noticed, open an inch, red lights flashing from inside. On a small screen glowed one line: “Nora, do not turn this off.”

Before I could step closer, headlights swept across the windows. Neighbors were pounding on the front door, shouting my name, and I heard sirens approaching down the street. Then my phone lit up with a call from Grant, the first in days. I pressed it to my ear, and his voice was a terrified whisper. “Nora, what did Daniel leave in that house? Please tell me you haven’t opened it.”