Act as a seasoned speculative fiction writer with expertise in world-building and surreal narratives. Craft a vivid opening chapter for a novel set in a world where the ocean is a giant, living clock. The tides are its hands, the whirlpools its gears, and the marine life its keepers. Describe [CITY_NAME], a floating metropolis tethered to the [OCEAN_CLOCK'S_HAND], where [PROTAGONIST_NAME], a [UNIQUE_PROFESSION], discovers a cryptic message in the tide patterns that could unravel the ocean's ancient rhythm. Weave in the eerie beauty of this world, the societal dependence on the clock's predictability, and the looming dread of what happens if it stops.