In a world reconstructed by the legendary clockmaker Y after Earth's destruction, Naoto Miura dreams of becoming a renowned clockmaker. Blessed with a rare gift of acute hearing that deciphers clock mechanisms through sound, Naoto struggles to make significant advancements. Everything changes when a mysterious coffin crashes into his dwelling, unveiling RyuZU, an exquisite automaton crafted by Y. The unexpected arrival of RyuZU attracts the attention of Marie Bell Breguet, a skilled clockmaker heiress, and her cyborg protector Vainney Halter. As Naoto, Marie, and Vainney are thrust into a perilous struggle for survival, they unearth a chilling reality: the clockwork planet sustaining humanity for centuries is deteriorating, a dangerous truth that certain individuals will go to great lengths to conceal.