The Great War of Archimedes

In 1930s Japan, mathematician and autistic prodigy Major Tadashi Kai (Masaki Suda) discovers discrepancies between official cost estimates and actual figures for the construction of the world's biggest battleship, Yamato. He teams up with Admiral Isoroku Yamamoto to uncover a conspiracy, learning that the ship's true purpose is to symbolize Japan's collective spirit, making its loss so traumatizing that it will lead to surrender before invasion.