Lucius Modestus, an architect from ancient Rome, struggles to conjure up fresh ideas and finds himself on a job hunt. His glum demeanor and personality attract concern from his friends who persuade him to visit a bathhouse to unwind. However, the bustling and crowded atmosphere fails to alleviate his worries. In a last-ditch attempt to relax, Lucius submerges his head in the water, and to his surprise, uncovers a hidden tunnel. The tunnel takes him to a modern Japanese bathhouse, and this encounter sparks his imagination and helps him create a new masterpiece. Though his new project feels centuries ahead of its time, Lucius attempts to recreate it, but his primitive resources prevent him from fully realizing his vision. Nonetheless, his ingenuity is enough to impress the people and earn him his well-deserved recognition as a talented architect.