Beneath the city, past a door no map remembers, sits a library that should not exist. Its shelves stretch farther than any flashlight can reach, and every book on them holds a name, a face, and a death that hasn't happened yet. When three strangers stumble into its silence, they realize too late that the library doesn't just record the dead. It chooses them. Mara Whitlock finds her own name buried on page one hundred. Daniel Cross finds his crossed out and rewritten in a hand that isn't his. And on the last shelf, in the last row, waits the final volume, still being written, page by page, in real time. Its subject is a man named Ethan. He has not read it yet. He has no idea it is already finding the words for how he dies. As the three of them race to understand the rules of this place, they learn that closing a book means erasing a life, and that something below the library has been waiting a very long time for the right readers to walk in.