Ookawabata Tanteisha sets up office along the Sumida River. This detective agency is very small, with only Receptionist Megumi, Investigator Muraki, and the Director. The first client is Wakagashira Yabe, who is concerned about his dying boss. He boss only wants to eat wontons from the culinary visionary Cho Raku in the Asakusa district. However, the wontons have made hime deathly ill, and Cho Raku is already out of business.
