Dead Bird Mask was placed in charge of a plot to excavate a feudal treasure buried around Matsuyama Castle on the island of Shikoku, in hopes of using it for Golden Mask's plot of building the golden castle for the Black Cross Führer. After an attempt to steal a buddha which is part of the treasure, the Gorengers head to Shikoku using a clue they receive to try and figure out where it is located before it is fully excavated. However using their original clues regarding the Shikoku Pilgrimage and the site where the gold was supposed to be, they initially don't find it until they compare it with a tourist map of Shikoku, discovering the locations and thus the location both of the treasure and of Dead Bird Mask.