Thorne Vance woke on wet sand with no pulse and no name for this shore. He had drowned once already. The obsidian on his arms told him the storm had not finished with him. Black stone crept to his elbows and up the left side of his neck, cool and hard. Across it, maps he never drew slid over his skin like oil. He was a cartographer who could no longer trust his own charts. Somewhere those shifting lines pointed to a drowned library, every lost fact of the sea sealed inside. He meant to reach it before the stone reached his heart. He pushed himself up and read his own arm. The map showed only fog. Coastline, current, depth—all of it blurred and useless. He knew why. The charts sharpened only near old landmarks. Here he saw nothing but blank sand and gray water. Without a fixed point, he could not tell which coast he had washed onto, or which way the library lay. Something tugged his boot. A small crab pup clung to the leather, fluffy and rainbow-striped, one pink claw pinching his lace. It chirped and hopped back, then darted a few steps up the beach. It stopped. It looked at him. Then it ran again, claws clicking, as if leading. Thorne followed. He had no better plan. The crab pup scrambled over a dune and stopped at a heap of stone. A lighthouse stood there, or what remained of one. Cracks split its tower. A jagged hole gaped in its side. Paint peeled from the old brick in long curls. No light had burned in it for years. But it was a landmark. It was old. His arm answered at once. The obsidian flared. Salt cracked along the veins and stung like a fresh cut. Thorne hissed and gripped his wrist. The pain was the price; every secret his skin gave up, it charged in stone and ache. He held still and let the map draw itself. Lines spread from the ruined tower. A coastline formed. He read a long southern reef, a bay of black rock, a harbor town two days' walk east. He knew this place now. He knew where he stood. A pale shape rose in the shallows below. An albino octopus lifted one translucent tentacle from the surf. It pointed—not at the town, not at the reef, but out to open water, where the map on his arm ran off his skin into nothing. Then it sank without a ripple. Thorne looked from his charted arm to the empty sea. The lighthouse had given him his position. It had also shown him the truth he did not want. The library lay off the edge of every landmark he could reach on foot. To read further, he needed more old places, and each one would cost him more stone. He wrapped his aching arm and started east, toward the harbor, and toward the next ruin that could speak.