Kinshiro Toyama sends Tenho and Tenten to follow the old man in the streets, in order to investigate his real identity. Tadakuni Mizuno soon orders Torii and Toyama not to approach the old man, not knowing they have already done so. When Tenho and Tenten arrive at the old man's home, finding many occult relics and items in a chamber. When Ginjiro finds them from outside, the two hide inside the chamber, only to be turned into cats. It is also found out that Seikichi and Sora have previously turned into cats as well. The old man returns and zaps the four back to their original forms. Toyama also arrives to clarify the reason behind his orders. Though Tenho and Tenten had intended to protect Seikichi and Sora, they are asked to leave the row house, however they first enjoy a cookout planned by the residents.
突然、清吉とソラの姿が見えなくなった。さらに、かげ富の件、風来長屋の修繕の件など、事件のもみ消しに一役買っているご隠居の調査のために二人の部下を送り出す北町奉行・遠山金四郎。だが、隅のご隠居の屋敷内に忍び込んだ二人は、屋敷の外見からは想像も付かないおどろおどろしい研究施設を目の当たりにして…。
