Michio Yuki has it all: looks, intelligence, a pedigree as the scion of a famous Kabuki family, a promising career at a major bank, legions of female admirers. But underneath the sheen of perfection lurks a secret with the power to shake the world to its foundations. During a boyhood excursion to one of the southern archipelagos near Okinawa, Yuki barely survived exposure to a poison gas stored at a foreign military facility. The leakage annihilated all of the island’s inhabitants but was promptly covered up by the authorities, leaving Yuki as an unacknowledged witness—one whose sense of...