Arson Theft Control struggled to investigate Gohei Ishikawa, a member of a notorious clan led by Shinbei the Viper. As a child, he was abused by his step-father. While Heizo was in Kyoto, the abuse escalated and led to him stabbing his step-father to death. He ran away from Edo and resented Onihei for the incident.
火盗改たちは、悪名高い「蝮まむしの新兵衛しんべえ」の一味として捕らえた石川五兵衛の取調べに手こずっていた。五兵衛の顔を見て、平蔵の記憶が蘇った。「あやつ、音松か!」 音松は子供の頃、継父から虐待を受けており、「何かあればすぐ役宅に来い」と平蔵が度々助けたが、役目で平蔵が京にいる間に継父の仕打ちはさらにひどくなり、ついに刺殺、江戸を飛び出してしまい、「それも鬼平のせい」と逆恨みしていた。
Il Controllo Incendi e Furti indaga su Gohei Ishikawa, membro del clan di Shinbei La Vipera, che da piccolo fu vittima di maltrattamenti da parte del patrigno. Mentre Heizo si trova a Kyoto, le violenze peggiorano sempre più finché il ragazzo pugnala il patrigno uccidendolo. Scappando da Edo, incolpa Onihei per l'accaduto.