“The Dog with Vanishing Spots” is a 1939 work of detective fiction by Miyano Murako. One of only a few women writers of detective fiction in the prewar period, Miyano presents a work in tune with the state of the genre during its Golden Age, while also displaying the interest in character psychology that figured prominently into her writings. The result is a mystery of lost dogs, stolen jewels and murder in the continental city of Dairen, all centered on a character that just might be the lone instance of a teenage female sleuth in Japan's prewar detective fiction canon.