Kyousuke has been arrested. Hagiwara Sakutarou, Nomura Kodou, and the others gather at the "milk hall," a small cafe serving European beverages and foods, to try to discover the truth of the situation. Each of the literary men unveil their deductions. Natsume Souseki introduces Akutagawa Ryuunosuke who also participates in the puzzle solving, but none of them come up with a deciding theory. As they ponder, a boy named Hirai Tarou steps forward. Hirai tells them that everything started two nights ago...