Bungou Stray Dogs: The Secret Story Behind the Detective Agency's Establishment

The story tells the meeting of Yukichi Fukuzawa, who was then doing bodyguard jobs in Yokohama, and the young, mysterious boy Ranpo Edogawa, who instantly solved the murder of one of Fukuzawa's clients. Fukuzawa and Edogawa's strange meeting leads to the establishment of the current Detective agency.